Mathematical "urban legends" - <AUTHOR> http://mathoverflow.net/questions/53122/mathematical-urban-legends <comment><USER2> Since the thread there seems locked, I'll add:

I would be surprised if the snarky Ivy League mathematician from Japan was Hironaka. He was much too gracious for that, including in that he overpraised my thesis to my parents at my thesis defense.

Dean Yang's conjecture about Andy Gleason getting calculus onto the qualifying exams was very credible. I'll add the story that a significant fraction of Harvard math grad students passed their qualifications conditional on an passing a later oral exam in one or two sub-disciplines. Joe Harris' conditional was said to have been on calculus.

A Bulgarian visitor (this was in the 1970s) told me that all university graduates in his country, or at least in his university, had to write a senior thesis on applying Marxist-Leninist thought in their disciplines. He didn't go on to explain how he'd done this in mathematics.

A visitor from, I think, the UK had rock-star style long hair. It was set on fire by a candle at wine and cheese. I'm pretty sure Raoul Bott was the guy working most closely with this visitor, which was regarded as funny since he seemed a bit square in such respects.

I heard the Milnor story from Nick Gunther, who'd been a Princeton undergrad. Nick was a heck of a story-teller in general. (His father was John Gunther, of Death Be Not Proud fame.)

I have no stories about Andrew Wiles. He was quiet and polite.

Mackey was a character. I find the story believable.

Zariski's 80th birthday conference included a new paper by him, if I recall correctly.

<comment><USER2> OK. I've gotten to the Ofer Gabber part now. Ofer was in my dorm, and indeed had the room next to mine. That dorm held a pajama party at midnight. At the party, he tried to engage me in mathematical discussion.

We had a bit of a math kid's row there. I started grad school at age 16. My roommate Ran Donagi started at 17. Ofer started at 16. I think they both were a lot more accomplished in math on arrival than I was, however, so that makes me the least precocious of the three of us. :) Perhaps not coincidentally, I'm the one who didn't remain in mathematics.

<comment><USER3> Please please please tell more Gabber and Donagi stories.

(Every time I stumbled upon an "unproved theorem of Gabber" in a paper, I would take a screenshot and throw it into a folder.)

<comment><USER2> Apparently the Putnam exam was given unofficially to Israelis, and both Ran and Ofer finished top 10 -- in their mid-teens. By way of contrast, my best finish was a little worse than 100th, when I was 14.

Ran was 3 years ahead of me, and pretty much the ideal roommate (my second semester; I invited him to swap rooms with a first semester roommate I didn't much get along with). No hassles about living conditions; some older-friend general advice; a lot of help studying for my qualifying exams.

Ran had a sadness about him due to political controversy -- he had gotten a special postponement of army duty due to his precociousness, he didn't want to go back to fulfil his commitment, and orthodox Jewish department chair Shlomo Sternberg pretty much expelled him (albeit with a PhD) in retaliation.

Of course, a much greater sadness later occurred in Ran's life, as his ex-wife killed their child in a murder-suicide. :(

Ofer was a stereotypical geek; Ran was a more socially adept guy, with girlfriends and so on. Not coincidentally, he spoke the much better English of the two.

If we had a hierarchy of who was quickest and smartest in the department, the top two were generally thought of as Ofer and Angelos Tsiromokos. In reality, Don Coppersmith was right up there as well. Angelos of course is the one who never got his PhD, instead going off to be a translator for the Common Market/EU. But then, he could beat me at Scrabble, despite English being his third language.

(On the other hand, Daniel Pipes, who briefly lived in my dorm, didn't take kindly when a math guy -- me -- took him down at a word game. :) )

Ran told me of a multi-day conversation in which guys progressed through the natural numbers, coming up with an interesting mathematical question to which the number was the answer. I think they got stuck at 93 or so.

When we were in the common room, it somehow came up in conversation that Jacobi was Jewish. I immediately said "Oh, THAT'S Jacobi's identity!" Angelos literally fell out of his chair laughing.

</comment></comment></comment></comment><comment><USER4> 1) One of my high school buddies who went to the Courant institute for his math Ph.D. defended his thesis and then it turned out his proof was one that his own advisor had completed 10 years ago in a side note to a publication of a bigger result. They still gave him the Ph.D. (and I think the advisor was reprimanded); he wound up in finance.

2) Although I'm a biochemist, I did a math degree at the UofC - one memorable lecture was the analysis class lecture where we proved that pi was irrational (Professor Carlos Kenig). It started with the assertion, "assume pi is less than 6". Then he said, "actually it doesn't really matter what the number is it still works, I don't know how to count past 2, I'm sure 6 is big enough."

<comment><USER5> I'm surprised he can count to 2. In CS it's just 0, 1, infinity.

<comment><USER4> He works in L2 spaces.

[http://math.uchicago.edu/~cek/bibliography.pdf](http://math.uchicago.edu/~cek/bibliography.pdf)

<comment><USER6> That must be a difficult commute each day from R3 space.

</comment></comment></comment></comment><comment><USER7> MathNews, UW Math department's student weekly newsletter, had/has a section 'profQuotes' \- just about the only part worth reading.. samples from this week:

"Tragically, we will need to prove both cases. Fortunately, I can do one in class and assign the other for homework."

"I'm sure you're familiar with the proof technique I'll use here... [writes 'Exercise' on the board]"

<comment><USER8> What's their issue with pretzels? :P

</comment></comment><comment><USER9> Somewhat similar to some of the posted ones, my father relays me this story about a professor he TA'd for:

The professor taught a class with a single student enrolled, who would sometimes show up late. However, the professor would always start the lecture on time regardless, and so the student would have to quickly take notes to catch up. If the professor filled up the board before the student arrived, he would simply begin overwriting the old material, and the student, once he arrived, would be in a race with the professor to copy it down before it was erased. One day, the student missed the class entirely, and the professor gave the entire lecture to an empty room.

I thought this story was apocryphal, but my dad said it's likely true, as it was fairly specific about this professor.

<comment><USER10> Not quite the same, but one of the math professors from my alma mater could write faster on a blackboard than most people could write with pencil and paper and was not shy about erasing when he filled up the board. It was always crazy trying to keep up with him.

<comment><USER11> I remember a prof, I think math, might have been physics (there was one guy in the physics department whose MSc was in mathematical physics, was working on his PhD, taught in both departments, and seems to my shaky memory to be the best match for what happened) who actually had the eraser in the "other hand" one day, applying it as he went. I think he was just excited, cannot remember why. One or more us said something like "uh, professor...?", he noticed, put down the eraser, and continued, somewhat sheepishly.

</comment></comment></comment><comment><USER12> I propose a new Law of SE: any topic of interest will eventually either get rejected or locked for being historical only.

<comment><USER13> That makes a lot of sense, right? Stack exchange is designed around making it easy to find and get good answers to questions, not to have more involved or less focused discussions, even if they're more interesting to read.

<comment><USER14> The problem with this is the Law of Internet Monopolies (I just made the name up): monopolies on the internet form very naturally and are tough to dissolve.

The sheer size of stackoverflow/mathoverflow means it attracts many mathematicians in one place, unlike almost any other online forum I know. If you restrict some subset of questions there, it is both impossible to look for such questions elsewhere (nobody goes elsewhere) and to create a trivial fork of mathoverflow where such questions are allowed (you'll never get critical mass because people will not spend their time on two similar websites).

It's the same reason why nobody can create a better Wikipedia, no matter how much pointless arguing is on the original and how clunky is the input editor.

\---

To sum up, restricting questions on MO actually _forbids_ such questions to be asked by a large online mathematical community for a few years, until some better Q&A forum appears. And that's what makes us upset, I think.

<comment><USER15> I recently had the experience of listening to Joel Spolsky talk on the subject of seemingly arbitrary and unintuitive rules in large internet communities. Basically what I gathered from it is that in order to keep the quality of the content at a higher level, some of these rules are the best ways that this can happen. Some of these rules sound dumb, but they come from the experience of actually moderating very large communities and still trying to maintain focus on the actual goal of the site. As for your concern on this seemingly monopolizing the space of mathematicians I think this is untrue. If the demand for a place to discuss this content exists enough to have a critical mass community in the first place, surely it can exist outside of stack exchange. There is no overlap there because that is not at all the same content that stack exchange is hosting. I can certainly imagine a scenario in which I would frequent one site to answer and receive answers on questions in mathematics, but also frequent a board for casual community driven math topics.

<comment><USER14> _> I recently had the experience of listening to Joel Spolsky talk on the subject of seemingly arbitrary and unintuitive rules in large internet communities. Basically what I gathered from it is that in order to keep the quality of the content at a higher level, some of these rules are the best ways that this can happen._

I understand the creators must have _done something right_ , but I believe it is chiefly the tight UI (focus on questions instead of posts that get hidden over time) along with the strong gamification (you get a lot of power if you amass points) that kept the early adopters hooked, thereby gaining enough mass for the site to become popular.

The tightness of the questions is for me just a quirk of the creators' personalities. Look at Reddit -- also partially gamified, very loose with its rules, and massively popular. If the rules were the magic that makes or breaks fora, Reddit would never have made it.

 _> If the demand for a place to discuss this content exists enough to have a critical mass community in the first place, surely it can exist outside of stack exchange._

I disagree. If you look at this discussion and many others, you'll see people expressing their discontent about questions being forced out of MO/SO. Do you think the people that complain do not want such a place?

<comment><USER15> In response to the comment on Reddit, Joel mentioned this in one of his points. His response related to the part where I mentioned maintaining a high level of quality in the content. It's not that everything is bad on Reddit, but it sure is easier to filter out the bad when we have these rules on what belongs and what doesn't. In other words, things must be sacrificed if you want to have lower troll density. Even HN has it's rules, even if they are community driven at this point, but that's how many of these rules begin on other sites (citing Joel's experiences with SO and his knowledge about wikipedia).

I don't think casual fun interactions should be banned on the internet, it's just more likely to involve undesirables that certain websites are a million times more effective by avoiding. Imagine if you searched up a question on MO or SO and the first number of responses were bloated indefinitely by other answer threads discussing the topic, but maybe not in the same context, their website becomes that much more ineffective for it's desired purpose.

As far as not seeing a place and the discussion on it, I think that is more indicative of the fact that people would like a place, but nobody has been particularly motivated enough to make it happen yet. Not to mention, at least currently you can get a similar discussion by linking the historic thread on a comments section with upvotes, so it seems another competitor for that community would be sites like HN and Reddit rather than MO where you can't post on it anymore.

Edited for spacing

</comment></comment></comment></comment></comment></comment><comment><USER16> I've heard the one where the professor is lecturing, and says, "It's obvious that..." A student challenges him: "Come on. Is it really obvious?" The professor looks at the board for a moment, and then runs out of the room. 45 minutes later, the professor returns, and says, "Yes, it's obvious."

<comment><USER8> Reminds me of this Feynman story:

[http://pastebin.com/rW2QU5k7](http://pastebin.com/rW2QU5k7)

 _"We have a new theorem–that mathematicians can prove only trivial theorems, because every theorem that's proved is trivial."_

Not very related perhaps but I think this is a great quote:

 _So I got a great reputation for doing integrals, only because my box of tools was different from everybody else's, and they had tried all their tools on it before giving the problem to me._

<comment><USER6> I love this!

</comment></comment></comment><comment><USER17> Unfortunately I don't have any reputation on MO to post this story.

On the first math class during 5th grade our math teacher (who was giving her first class after Graduation) spend about one hour talking about how mathematics could be challenging and another hour talking about her thesis (now I know, at time I wasn't understanding a shit)

Once she finished her non-sense lecture, she dictated us our home work.

"Go to the library and find what's Pie"

With a couple of classmates we spent our afternoon on the public library's culinary section writing our essays about measuring pies.

</comment><comment><USER18>
       Here's another great one: a certain well known mathematican, we'll call him Professor P.T. (these are not his initials...), upon his arrival at Harvard University, was scheduled to teach Math 1a (the first semester of freshman calculus.)

       He asked his fellow faculty members what he was supposed to teach in this course, and they told him: limits, continuity, differentiability, and a little bit of indefinite integration.

       The next day he came back and asked, "What am I supposed to cover in the second lecture?""

The funny thing about this is that we covered all of that in a total of 6 hours (2 hours per day) during my first year in CPGE.

<comment><USER19> The non-funny thing is 99.99999999% of people won't understand the basics of calculus is such a time span.

<comment><USER18> That's when personal effort kicks in, 6 hours of courses followed by, say 18 hours of working on exercises, proofs and problems, will get you going.

</comment></comment></comment><comment><USER20> Hah. I thought: "That sounds like an interesting topic. How could it have escaped Stack Overflow's ruthless prohibition against interesting reading?" And of course it hasn't.

</comment><comment><USER21> I was once taking a class with Csaba Szabo in Hungary, who, as usual, was writing furiously on the board, when the quietest student in the class raised her hand. Without turning around, Csaba yells, 'YES, QUESTION?!'

The girl says, 'Csaba, what's going on with you? You're always yelling, you slam the boards down, throw chalk constantly... Last week you even broke a window? Why are you so angry?'

Csaba responds, 'Yes, yes, angry always. A storm is coming, and algebra is the thunder!'

</comment><comment><USER22> It boils my blood every time that I come across an interesting topic on SO just to see it locked. Something is wrong with the site when you see more topics locked than open.

<comment><USER23> Locked is all right, maybe it has the answer you're looking for. The shitty part is when you get a hit from google going to SO and the SO page is _deleted_ because "this problem is too localised and unlikely to happen twice".

<comment><USER24> This is a trend in Google search results for forum threads. Especially common (and frustrating) is getting a link to a locked thread with a single response telling the OP to search for the answer to their question.

</comment></comment></comment><comment><USER25> There is this no nonsense, star faculty in the department where I did my undergrad.

Urban Legend in the department says that in one of the offerings of his classes, there was this smug student, who would chime in, and comment on the material being presented at every chance he got.

One day, while the faculty was presenting a particularly tough topic material to the class, the smug student raised his hand and asked, "Would it be OK if I ask a stupid question?"

The faculty looked at the student's face, grinned and said, "It is perfectly fine. After all, there is nothing such as stupid question." He paused for a bit, and then completed his sentence. "But there is only such a thing as stupid student."

</comment><comment><USER26> In the same vein:

In my Physics undergrad, a teacher called a friend of mine to the board and asked him to write Snell's law.

He picked up the chalk and wrote "Snell's law".

<comment><USER27> This sounds like a parable for CS about the importance of quoting.

</comment></comment><comment><USER28> Can someone explain the introductory story? Why is it significant that the spaces were finite?

<comment><USER29> From my recollection of topology, finite spaces are mostly useful as demonstrations or counter-examples. So, to illustrate a point about why something isn't true, you might break out a finite space to provide an easy- to-understand means of grasping the counter-example (there's an entire book called _Counterexamples in Topology_ for this purpose).

"Real work" in topology generally involves infinite spaces, though.</comment></comment>


Beware of Complex Filtering in GraphQL - <AUTHOR> https://graphqlme.com/2018/05/05/beware-of-complex-filtering-in-graphql/ <comment><USER2> While trying to understand GraphQL, this kind of filtering was the first thing was what I was hoping would be easily possible. I don't agree that creating such a filter is complex for the client or that is is an unreasonable expectation that the client would want to.

As an example, the OData spec has query filters: [http://www.odata.org/getting-started/basic- tutorial/#queryDa...](http://www.odata.org/getting-started/basic- tutorial/#queryData)</comment>


Climate deniers get more media play than scientists: study - <AUTHOR> https://phys.org/news/2019-08-climate-deniers-media-scientists.html <comment><USER2> Link to the original article, strangely absent from this piece: [https://www.nature.com/articles/s41467-019-09959-4.pdf](https://www.nature.com/articles/s41467-019-09959-4.pdf)

They include politicians and business people in their analysis, and though they do acknowledge it as a shortcoming, they don't really do anything substantial to mitigate it.

Also, their analysis is really all over the place. It's not clear exactly how they're testing their hypothesis, they're just gathering a bunch of data and creating a bunch of pretty figures. Their "contrarian" list is kept private, so it's hard to know what they're really measuring. They put a ton of emphasis on using citations as a measure of scientific authority, but are using a dataset where they put politicians and business people in one group and exclusively scientists in the other group. There are plenty of climate change advocates who aren't scientists, why couldn't they match the two groups?

This is a perfect example of an increasing trend where it seems like the headline of the popsci article covering the research was written first, then a "scientific study" was performed in order to generate the headline desired.

</comment><comment><USER3> I guess the deniers have much more time to spend on media, since they aren't busy with researching, evaluating, predicting and trying to come up with solutions.</comment>


Creating sustainable competitive advantage - <AUTHOR> http://sethgodin.typepad.com/seths_blog/2009/10/creating-sustainable-competitive-advantage.html <comment><USER2> "No successful web company (not eBay, Flickr, Amazon, Facebook...) succeeds because of a significant technological barrier to entry. It's not insanely difficult to copy what they've done. Yet they win and the copycats don't."

Amazon had billions of dollars in losses before they were profitable; that's a huge barrier to copying what they've done. Not to mention their logistics/tracking technology. You can't run a company like Amazon or Walmart without incredibly advanced supply-chain management, etc.</comment>


San Francisco Is So Expensive Even Renters Can Be NIMBYs - <AUTHOR> http://www.citylab.com/housing/2017/02/renters-in-expensive-cities-are-all-about-nimbyism/516021/ <comment><USER2> Isn't rent control a big part of this? Does the effect persist in non rent controlled cities?

Though actually, thinking about my own feelings, as a renter in an expensive and non rent controlled city (Sydney) I would be opposed to any major development nearby. It's unlikely to materially lower my rent, but is likely to lower the overall quality of the neighbourhood (crowding, traffic, shadows, and the general ugliness of new apartment buildings).

Now, I'm not saying that the fact that I oppose it means that I have any moral right to stop it, but it's not surprising that renters should oppose development too.</comment>


Why Self-Track? The Possibility of Hard-to-Explain Change - <AUTHOR> http://quantifiedself.com/2012/08/why-self-track-the-possibility-of-hard-to-explain-change <comment><USER2> I have to admit I cringed at some of the examples provided, as well as the associated causal evidence.

1\. Eating Fruit for Breakfast => Reduced Sleep Quality [in fact, " _...I figured out that any breakfast, if eaten early, disturbed my sleep_ ".

2\. Removal of Mercury Fillings => Improved Brain Function. The evidence was surprisingly lacking :

"The evidence for causality — removal of mercury amalgam fillings improved my arithmetic score — rests on three things: 1. Four other explanations made incorrect predictions. 2. The improvement, which lasted months, started within a few days of the removal. Long-term improvements (not due to practice) are rare — this is the only one I've noticed. 3. Mercury is known to harm neural function ("mad as a hatter"). As far as I'm concerned, that's plenty."

I am all for self-observation, but I can't help but think that some of the causal links the OP has established may not be particularly well founded.

<comment><USER3> If this was the only writeup Roberts ever produced, the cringing would be well deserved. However, he does have a long history of correctly quantifying changes in himself and identifying their source.

Specifically, his (on its face, ridiculous) shangri-la diet works well for 80% of the people -- probably better than any other diet (Although it should be noted that about 20% of people who try report it does not work at all).

Also, his flax seed, butter and vitamin D results have been replicated consistently by many (though again, not all). You can wait 15 years until these things get verified/shown wrong, or just try them yourself.

And about "well founded" - it's easy to dismiss some guy on the internet (regardless of his track record and academic qualifications, as this particular writeup was not done in the context of these qualifications). But you should be aware of your confirmation bias - e.g., if you ever considered any of the examples I give here <http://news.ycombinator.com/item?id=4427910> well founded.

</comment></comment><comment><USER4> "Professional scientists almost never use this method."

That's because of confirmation bias. All of his examples seem to be:

1) Experience a 1 to 2-sigma variation in normal performance.

2) Look for something different in what you did that day.

3) Keep doing that, and voila, a minor improvement.

You'll find yourself doing some pretty goofy things if you follow his suggestion too regularly.

Edit: misspelling/layout.

<comment><USER5> _You'll find yourself doing some pretty goofy things if you follow his suggestion to regularly._

Isn't that what science is? It may be biased, and it's very hard to isolate variables, but by the very nature of self-experimentation it's very difficult to do double blind tests. At least some people are trying to live the examined life and look for causes, rather than blaming it on genetics or luck.

<comment><USER6> He gets to the "hypothesis forming" stage, and draws a conclusion. That's fine if you're trying to figure out how to live your life best. The negative consequences of removing his mercury fillings are probably null, he can accept his hypothesis as true and move on. But this is _bad science_ , without question. We don't know that his mental function has improved because of removing fillings... it's a potential hypothesis, sure, but to say "Mercury Damage Revealed by Brain Test" in a headline seems a bit bold for a sample size of n with no control and a bunch of other confounding variables at play.

<comment><USER5> Yes, he does seem to pull out the "jump to conclusions" mat a bit much. That being said, I can't help but think that this would only justify more data. Log more variables; have someone review your methodology; etc. I've always wondered, how do you test your own intelligence? If you're writing and scoring the test, doesn't that invalidate scores you get? Ditto for taking the same test more than once. Maybe I'm just not smart or creative enough to think of ways around this (is that a test? :)

<comment><USER3> > I've always wondered, how do you test your own intelligence?

He is not measuring intelligence; He's measuring reaction times (how long he takes to solve a very simple arithmetic problem; or how long he takes to see which letter in a 4 letter string appears twice) and fine balance/motor function (how long he can keep his balance on an unstable platform he has built)

He went over these things in his blog in great detail over the years. He keeps trying new tests, keeps using those that are statistically stable in a "stable" environment (without changing nutrition / sleep / etc, and after a learning period) - and after he has a statistically significant baseline, he measures how e.g. eating more butter or flax oil changes the results of these tests.

Yes, this is drawing conclusions for n=1, but for himself, these conclusions are very scientific - and us humans are not unique enough for them to have wider applicability.

No, you cannot deduce from n=1 to the entire human race. Yes, his conclusions are plausible and most of them are verified by others. Read e.g. gwern.net on vitamin D.

<comment><USER7> I'm sorry, but science is neither "we measure the things" nor is it "we look for the cause." Yes, those are things which scientists do, but no, that is not the essence of science.

There is no attempt being made to come to any wholesome understanding. That is, a scientist is trying to model nature, and this consists in two parts: (a) develop a model, (b) test it against nature. Seth Roberts has perhaps hit upon a way to develop models, but he doesn't seem to test them. That is, _cum hoc, ergo propter hoc_ \-- "with this, therefore because of this" -- is not actually a _test_ for causation, but merely a _guess_ for causation.

To do a proper test, you need _variable isolation_ , and the _stability_ of test results is no guarantee that it is an isolated variable. A good example of an isolated variable is a simple light switch. A terrible example of an isolated variable would be your time of waking up, because that time cannot be isolated from your own thoughts and beliefs -- that is, many people, especially if they're not sleep-deprived, can wake up earlier simply by telling themselves "I'm going to wake up early tomorrow." (I myself usually wake up before my alarm clock goes off.)

Humans in general are not light switches. As has been documented repeatedly in medicine, dual effects of placebo and hypochondria plague us; things we expect to be medicinal often placate us even when they have no medicinal content and you can suddenly feel the symptoms of a malady soon after reading about it on Wikipedia.

So even if you want to say "for himself, these conclusions are very scientific," you're going to have to account for the problem that he is probably going to confirm whatever he already expects. That is, any "follow up" tests after the first guess are already tainted by the fact that _Seth knows what's being tested_.

<comment><USER3> > There is no attempt being made to come to any wholesome understanding

Do you actually follow Roberts, or is your understand based on this one short summary? Because, e.g. "What Makes Food Fattening" (77-page pdf here [http://media.sethroberts.net/about/whatmakesfoodfattening.pd...](http://media.sethroberts.net/about/whatmakesfoodfattening.pdf) ) is very much an attempt to come to wholesome understanding, develop a model, test it against nature. (The test is "putting it out in the wild", and the result is "works beautifully for 80% of people who try, not at all for the remaining 20%". He's not funded to test this, nor is he making any money of it - I don't think there's a better route for him to take).

> To do a proper test, you need variable isolation, and the stability of test > results is no guarantee that it is an isolated variable

Yep. Except, in the real world, NO published result related to nutrition, and almost no published result regarding medicine, is a proper test with isolated variables. Including almost every guideline your doctor works by.

> that is, many people, especially if they're not sleep-deprived, can wake up > earlier simply by telling themselves "I'm going to wake up early tomorrow." > (I myself usually wake up before my alarm clock goes off.)

That is true. And yet, a lot of people want diets to work, and they don't. A lot of insomniacs want a placebo to work, and it doesn't. Placebo is powerful, but is not all-powerful. It is stronger with some people, weaker with others.

Discarding results just because they were not the result of a double-blind placebo-controlled test is not rational. Neither is accepting results just because the author thinks that they are double-blind placebo-controlled:

e.g., almost all placebos today are sugar pills; If the tested-against- material has a side effect, such as causing flushing or a dry tongue (though does not produce the wanted outcome -- which is very often the case), this is not in face a double-blind; the patient knows that they did not get a placebo, and the whole test is useless. Yet, this is the gold standard.

Furthermore, if you read the NEJM / BMJ / Nature / Science medical papers, you'd notice that their result are tested on (and are therefore only valid for) a small ethnic group, a small age group, etc. But then, very unscientifically, it is assumed (by others -- usually not by the authors of said paper) to apply much more widely.

> That is, any "follow up" tests after the first guess are already tainted by > the fact that Seth knows what's being tested.

Yes, that does not make the results any less true or useful: Butter makes seth faster at arithmetics, in a consistent and statistically significant way. That may not be true for others. And may be entirely a placebo. Nevertheless, if Seth wants to be faster at arithmetics, he can do that by eating butter, regardless of the cause. Is that not science?

<comment><USER7> (1) Indeed, I am commenting on _this particular mode of understanding_ , where one keeps a journal, waits for a deviation of a test from normal, and then tries to correlate the journal with the deviations after the fact.

(2) "NO published result related to nutrition" is overbroad. Obesity for example is clearly related to nutrition and there are many published results where many variables which could affect obesity are quite well-isolated -- twin studies to isolate genetics, studies of how obesity rates vary based on physical location in various cities, and so forth.

(3) I aim to "discard the results" only insofar as they claim that they have measured an _agentic relationship_ , which these results have indeed claimed to measure. Seth's official conclusion is that this was "data that suggested butter improved my mental function." If the variable is not isolated, then attributing the agency to butter is worthless. It might have been an otherwise random variation at around the same time as he switched to butter -- the data he's describing has a 40ms variance as well as certain long-term patterns and the effect that he's describing is a 30ms improvement, so it's quite possible that in an autoregressive model you would just see one substantial "step down" of 80ms which doesn't get compensated due to hysteresis. Or perhaps the correlation is indeed correct but wrongly attributed -- perhaps Seth has not noticed but he tends to use butter to fry peppers and pork fat to fry meats, and now that he is using butter his diet contains 2% more vegetables. Perhaps now that he uses more butter, he eats more toast and gets 2% more fiber in his diet, without having written _that_ down in his journal.

The problem is precisely the word "makes" in your sentence "butter makes Seth faster at arithmetic." You have absolutely no evidence that it's the butter which is making Seth faster at it. And that is why the conclusion "butter makes Seth faster at arithmetic" is not a scientific conclusion.

<comment><USER3> > Obesity for example is clearly related to nutrition and there are many > published results where many variables which could affect obesity are quite > well-isolated -- twin studies to isolate genetics, studies of how obesity > rates vary based on physical location in various cities, and so forth.

Care to show me, for example, a single nutrition study where "skin color of participant" was a variable controlled for? It is known that cholesterol metabolism (eventually into) Vitamin D is greatly dependent on skin color -- and yet, it does not appear in a single nutrition study, despite the greatly known significance of both serum cholesterol and serum vitamin D.

I'm taking this ad absurdum in an attempt to show you that if you apply this standard rigorously (as one should), then no result really holds up.

And by the way, "obesity is clearly related to nutrition" is only true in the sense that "everything is related to nutrition". There are no results of things that affect obesity that are "quite well isolated" in humans that I'm aware of.

> Or perhaps the correlation is indeed correct but wrongly attributed -- > perhaps Seth has not noticed but he tends to use butter to fry peppers and > pork fat to fry meats, and now that he is using butter his diet contains 2% > more vegetables ...

If you actually followed him, you'd know that's not the case. He is very diligent about isolating variables as much as possible, and thoroughly documenting his day, including food intake, how much TV he watched, etc -- and the butter hypothesis was actually an attempt to strengthen a hypothesis having to deal with animal derived fats (which among other things, included bacon). It wasn't just observational - it was part of a variable isolation experiment, that (within limits) was comparably rigorous to any other non- blinded test (which are far more common than you'd think; in fact, many if not most supposedly double blinded tests aren't).

> You have absolutely no evidence that it's the butter which is making Seth > faster at it.

He has much more evidence for than you'd expect from this short posting, if you care to look at it. This conclusion is indeed supported by data, and is scientifically valid.

<comment><USER7> > Care to show me, for example, a single nutrition study where "skin color of > participant" was a variable controlled for?

<http://www.ncbi.nlm.nih.gov/pubmed/19656435> .

> I'm taking this ad absurdum in an attempt to show you that if you apply this > standard rigorously (as one should), then no result really holds up.

Then you should be willing to do what happens when a reductio ad absurdum fails: give up and admit you are wrong.

> And by the way, "obesity is clearly related to nutrition" is only true in > the sense that "everything is related to nutrition".

Uh, no. Obesity is a _nutritional disorder_ , as distinct from other things like having cats, which are neither caused nor hampered by good nutrition. What the hell are you smoking?

> He has much more evidence for than you'd expect from this short posting, if > you care to look at it. This conclusion is indeed supported by data, and is > scientifically valid.

I searched his website and all I could find was one particular crappy-looking graph with a bunch of discussion about his responses to vague questions, and an ad-hoc explanation (a competing omega-3 deficiency) when the data did not fit his expected pattern.

<comment><USER3> > <http://www.ncbi.nlm.nih.gov/pubmed/19656435>

Thanks. For some reason, I was unable to find this when I last looked (might have been before this came out).

> Uh, no. Obesity is a nutritional disorder, as distinct from other things > like having cats, which are neither caused nor hampered by good nutrition. > What the hell are you smoking?

> <http://www.medicalnewstoday.com/articles/249289.php>

Are antibiotics with no nutritional value considered nutrition these days? There are hundreds of substances that seem to cause obesity independent of nutrition (that is, when _isolated as a variable_ compared to nutrition), most prominently psychiatric drugs, but -- as is shown by this study -- also antibiotics, which are supposed to be "nutritionally inert".

Also, this was not shown in Humans and might not apply, but [http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjo...](http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001212) shows that obesity and type-2 like diabetes can result from gut flora. Are gut flora considered nutrition these days?

> I searched his website and all I could find was one particular crappy- > looking graph with a bunch of discussion about his responses to vague > questions, and an ad-hoc explanation (a competing omega-3 deficiency) when > the data did not fit his expected pattern.

He did not yet bother summarizing these results (the way he did for his weight loss theories, in [http://media.sethroberts.net/about/whatmakesfoodfattening.pd...](http://media.sethroberts.net/about/whatmakesfoodfattening.pdf) \- but there's a lot more discussion of it through the years) , I suspect that it is because he does not believe he nailed anything yet. However, he asks people to "try at home", and several of his results (mostly regarding dietary fat, but also about mood and sleep) have been confirmed by other people as well.

He's under no "publish or perish" stress like most papers you see, so he isn't trying to get anything production quality. I've been following him for 7 years now, and while it isn't blinded or double blinded, it's otherwise as good as (and usually better) than observational studies I find in top rated journals.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER5> Most serious athletes already know about this (in fact, on that same site: [http://quantifiedself.com/2011/03/personal-data- visualizatio...](http://quantifiedself.com/2011/03/personal-data- visualization/)). Keeping a record of your resting heart rate (plus blood pressure, temperature, etc) every morning will tell you many things. For example, I managed to get my resting heart rate down to mid 40s when I was training regularly (and heavily). Now that I'm more sedentary, my resting HR is in the mid 50s to low 60s, and I definitely don't feel as good or make as good times. Spikes while in training were also usually indicative of overtraining. It's also mentioned in "The Hacker's Diet" that if you weigh every day, but pay attention to the moving average it can be much more encouraging.

</comment><comment><USER8> But HOW do you track all that data? Today, with a smartphone, it seems easier, but even then I'd like something akin to a master spreadsheet that I can store it all in.

Seth: what format are you tracking all that data in?

Of course, now that I type that, I'm worried the answer is "pen and paper."

<comment><USER9> One of my someday projects to create a generic self tracking app that presents a dashboard for quick entry tracking and visualization and syncs with a website. It will also export to a spreadsheet. It will also allow you to visualize data with graphs and so on. There will be a bunch of presets for various special types of graphs, like with blood pressure and so on. You could also specify zones for numbers so you can show 'red' for a danger zone glucose level for example.

Managing spreadsheets on a smartphone is very kludgey.

<comment><USER10> That's basically a project I'm actively developing now - generic self-tracking (manual and via sensors and imported from other platforms), with presets and intuitive visualizations. This is a big gap in most tracking tools that are out there - letting you track anything you want, while also making sense of all the information in a useful way.

My motivation is to create something that's effective for sufferers of obscure chronic illnesses, since most tracking tools out there focus on major well- known illnesses, or simply aren't flexible enough to track weird symptoms that are so obscure that the developers have never heard of them. But the side- product is that the design will therefore be flexible enough to be useful for anyone who wants to track any element of their health.

<comment><USER11> Sounds really interesting, would you mind sending me an email? Im organizing the SF QS group and it'd be great to have you come and demo if you're local, and even if not we're looking for a tool to help us perform group QS tracking. My email is sina dot khanifar at gmail.

</comment></comment></comment></comment><comment><USER12> I love the QS movement, but I sometimes worry for it. It is young, and there is a wide variety of methodologies being used to draw conclusions, some are solid, others are far from it.

This can be expected from a group of people that have no requirements for joining, and this is a strength as well as a weakness. I have noticed that QS has attracted some "alternative [to] medicine" types who seem to be happy to have the validation, as well as some seriously interesting projects from hard core science types.

I am hoping that as this movement evolves, it will mature in the right way. Having amateurs participating is incredibly worthwhile, but guidance and best practices will hopefully develop in the community so that when people want to draw conclusions about causality, they can do it legitimately.

<comment><USER13> I feel the same as you, but the movement is evolving in the alt- med/pseudoscience direction really quickly. Amateurs are collecting tons of cool data (amazing!) and then doing their amateur analysis (Ancient Aliens level depressing!).

Without a very strong internal pressure to get their shit together and act like smart people who understand that some problems require expertise the movement is screwed.

</comment></comment><comment><USER14> Are we sure this isn't trolling? I mean _come on_ :

"Sleep and breakfast. I changed my breakfast from oatmeal to fruit because a student told me he had lost weight eating foods with high water content (such as fruit). I did not lose weight but my sleep suddenly got worse. I started waking up early every morning instead of half the time. From this I figured out that any breakfast, if eaten early, disturbed my sleep."

<comment><USER3> It isn't trolling. It's a short summary piece. If you are into these things, his blog and semi-formal papers ("what makes food fattening" and others) are a gold mine.

</comment></comment><comment><USER15> This is a method for hypothesis generation, but is not a valid way to draw inferences.

The reason why scientists don't draw conclusion from single data points (analogies) is that you can come up with flawed conclusions as a result. The changes could be purely random, or due to some other explanation that wasn't thought of.

In order of reliability: 1\. Do an experiment where an intervention is assigned at random, and scored by a method that is blind to the intervention (preferably on subjects who are blind to the intervention - but that is hard for some cases). 2\. Observe historical data where there have been many instances of each of the variables under study, avoiding correlation between variables with things like time. 3\. Use anecdotes.</comment>


I Lost My Life to Airbnb - <AUTHOR> https://narratively.com/i-lost-my-life-to-airbnb/ <comment><USER2> Personally, I think this is cool and props to the author for pulling it off. However, the thing that strikes the more scrutinous side of me about all this - the elephant in the room, if you will - is that what the author is doing almost certainly conflicts with her rental agreement and were she to be brought to court over it, it would probably be a clear case in the favor of the lessor and she might even have to pay back what she had earned. I feel like this is sort of the dream airbnb sells and here's a model case of someone achieving that dream but at the end of the day it's only possible because she's breaking a legal agreement; this probably wouldn't work if she were responsible for the higher cost of the mortgage and maintenance that comes with owning the property. In this case, the fan falls from the ceiling and she likely just calls her landlord to fix it. So the landlord assumes the cost to fix it and she continues to profit by subletting the apartment for significantly more than she's paying. Airbnb is basically facilitating a situation where the tenant gets to double dip. They profit off of an asset they don't own and don't assume much liability for and the owner is ultimately the loser. I wonder how this will all play out for airbnb on a larger scale over time.

<comment><USER3> You're right, and on top of that, her behavior artificially inflates rental prices (by shifting some of her rental costs to tourists).

In practice, illegal Airbnb's seem somewhat rare, especially compared to the millions of Ikea-furnished semi-professional rat holes that have taken over the platform.

There are tools that landlords can pay for that detect illegal sublets based on location and supposedly photos too.

<comment><USER4> Prices going up would be neither natural nor artificial. Some people would gain (the people renting and tourists) and others would lose (long term renters).

I think it's enough to say that it shouldn't happen without the landlord's consent.

<comment><USER3> > _Prices going up would be neither natural nor artificial._

By artificial, I meant that the rental market would be distorted by Airbnb hosts.

Good example: a friend of mine had parents who loaned him money to qualify for a lease. He couldn't afford the lease, so he used Airbnb to make up the difference.

This meant that non-Airbnb hosts were now competing with Airbnb hosts for the same leases, which is what I was labeling "unnatural".

<comment><USER5> In fact, anything anyone does to earn extra income to afford a better home distorts housing prices. It'd have the same effect if they made the same money running a software consulting business in their extra bedroom.

Housing prices in desirable downtowns are mostly distortion these days. It's been a long time since they corresponded to the cost of construction.

<comment><USER3> This isn't "starting a software business" \-- it's violating a lease.

Not everyone can or will take that risk.

<comment><USER5> In fact, many residential leases prohibit running a business out of the premises [0]. But these clauses are rarely enforced unless you're causing complaints.

[0] See clause 7 at [https://cozy.co/blog/8-important-lease-clauses-for- landlords...](https://cozy.co/blog/8-important-lease-clauses-for-landlords/) for typical terms

<comment><USER3> I lived in a condo building that fined an owner $60k for 2 years of illegal Airbnb leasing (for a $300k condo).

I also had a friend who was evicted for leasing a rental.

Running a business out of the premises is rarely enforced, but it also rarely creates risk or loss for the landlord the way Airbnb does.</comment></comment></comment></comment></comment></comment></comment></comment>


T * sin (t) ≈ Christmas tree (2013) - <AUTHOR> https://github.com/anvaka/atree# <comment><USER2> Hey, author of the project and the 2013 post here.

Just wanted to wish everyone amazing holidays! Thank you for love and shares :D

PS: More projects since 2013 can be found here: [https://twitter.com/search?q=from%3Aanvaka%20min_retweets%3A...](https://twitter.com/search?q=from%3Aanvaka%20min_retweets%3A20&src=typed_query) \- hope you enjoy it.

<comment><USER3> That vector field one is really neat.

[https://anvaka.github.io/fieldplay/?cx=-0.4690500000000002&c...](https://anvaka.github.io/fieldplay/?cx=-0.4690500000000002&cy=0.3672500000000001&w=15.8023&h=15.8023&dt=0.01&fo=0.998&dp=0.009&cm=1&vf=%2F%2F%20p.x%20and%20p.y%20are%20current%20coordinates%0A%2F%2F%20v.x%20and%20v.y%20is%20a%20velocity%20at%20point%20p%0Avec2%20get_velocity%28vec2%20p%29%20%7B%0A%20%20vec2%20v%20%3D%20vec2%280.%2C%200.%29%3B%0A%0A%20%20%2F%2F%20change%20this%20to%20get%20a%20new%20vector%20field%0A%20%20v.x%20%3D%200.2%20*%20%28%20p.y*p.y*p.y%20-%20p.x*p.x%20-%20p.y*p.y%20%2B%20p.y*p.x%20-%20p.x*p.x*p.x%20%29%3B%0A%20%20v.y%20%3D%20-0.2%20*%20%28p.y*p.y*p.x%20%20-%20p.y%20-%20p.x%20%29%3B%0A%0A%20%20return%20v%3B%0A%7D&code=%2F%2F%20p.x%20and%20p.y%20are%20current%20coordinates%0A%2F%2F%20v.x%20and%20v.y%20is%20a%20velocity%20at%20point%20p%0Avec2%20get_velocity%28vec2%20p%29%20%7B%0A%20%20vec2%20v%20%3D%20vec2%280.%2C%200.%29%3B%0A%0A%20%20%2F%2F%20change%20this%20to%20get%20a%20new%20vector%20field%0A%20%20v.x%20%3D%200.2%20*%20%28%20p.y*p.y*p.y%20-%20p.x*p.x%20-%20p.y*p.y%20%2B%20p.y*p.x%20-%20p.x*p.x*p.x%20%29%3B%0A%20%20v.y%20%3D%20-0.2%20*%20%28p.y*p.y*p.x%20%20-%20p.y%20-%20p.x%20%29%3B%0A%0A%20%20return%20v%3B%0A%7D)

<comment><USER2> Thank you! Amazes me how some people use it creatively to teach ordinary differential equations

[https://twitter.com/sxpmaths/status/1192079061025263616?s=19](https://twitter.com/sxpmaths/status/1192079061025263616?s=19)

</comment></comment></comment><comment><USER4> This one [0][1] is probably my favourite variation.

[0] [https://community.wolfram.com/c/portal/getImageAttachment?fi...](https://community.wolfram.com/c/portal/getImageAttachment?filename=tree.gif&userId=93201)

[1] Silvia Hao's reply at [https://community.wolfram.com/groups/-/m/t/175891](https://community.wolfram.com/groups/-/m/t/175891) (Also, why doesn't it have id attributes for individual replies?)

<comment><USER5> First idea I read title I thought about Mathematica and first comment is about Mathematica.

</comment></comment><comment><USER6> And in (quick and dirty) Python, with matplotlib:

        import numpy as np
        import matplotlib.pyplot as plt
        from mpl_toolkits.mplot3d import Axes3D

        fig = plt.figure()
        ax = fig.gca(projection='3d')
        theta = np.linspace(-4 * np.pi, 4 * np.pi, 100)
        r = 4*np.pi+theta
        z = -r
        x = r * np.cos(theta)
        y = r * np.sin(theta)
        ax.plot(x, y, z, 'g*')

        r2 = 4*np.pi+theta+np.pi/2
        z2 = -r2+np.pi
        x2 = r * np.cos(theta+np.pi/2)
        y2 = r * np.sin(theta+np.pi/2)
        ax.plot(x2, y2, z2, 'r*')
        ax.scatter3D(0, 0, 5, color='gold', s=200, marker="d")
        ax.axis('off')

:)

<comment><USER7> Add this line at the bottom to show the tree:

        plt.show()

</comment></comment><comment><AUTHOR> If this interests you, you should check out the bivector community [https://bivector.net/](https://bivector.net/)

Join the discord [https://discord.gg/vGY6pPk](https://discord.gg/vGY6pPk).

Check out a demo [https://observablehq.com/@enkimute/animated- orbits](https://observablehq.com/@enkimute/animated-orbits)

</comment><comment><USER8> Dumb question: In the code[1], the requestAnimationFrame() function is overwritten with a custom implementation using setTimeout(). From my understanding, this is done unconditionally, even if the browser provides the function (the reason is not a polyfill but having better control over the frame rate).

However, wasn't the whole idea of requestAnimationFrame() that it provides better timing guarantees than setTimeout()? So wouldn't overwriting with setTimeout kind of defeat the purpose of using it?

[1] [https://github.com/anvaka/atree/blob/58680a99113cc40cd07c371...](https://github.com/anvaka/atree/blob/58680a99113cc40cd07c3716dd81491c0f263486/index.js#L140)

<comment><USER2> The idea was to match animation speed of the gif and JavaScript implementation (which was 24 frames per second)

requestAnimationFrame() (RAF) is more likely to fire approximately 60 times per second than setTimeout(..., 1000 / 60) would. But I needed 1000 / 24, and setTimeout worked very well, so I used it.

If I were doing it all over again, I'd probably use RAF with window.performance, or simple counting variable as a timer. RAF is indeed much smoother than setTimeout and on top of it, RAF saves battery life when a user doesn't have your page open.

Good question!

<comment><USER9> What about using normal RAF and slowing the animation itself down to match the original GIF as best as possible?

<comment><USER10> I think that's what they were suggesting with

> If I were doing it all over again, I'd probably use RAF with > window.performance

Since RAF doesn't give a guaranteed framerate you'd need to use metrics from window.performance to make the animation framerate-independent, or people on different browsers or devices could see the animation at different speeds.

</comment></comment></comment></comment><comment><USER11> What kind of ingrate files an issue on a Christmas present?

<comment><USER12> I'm always grateful for all issues, on all repos, if the intention is to genuinely improve the project.

<comment><USER13> I usually agree, but two of the three open issues should really just be PR's :\

...

After typing that, I realized that this comment should actually just be a PR[1].

1: [https://github.com/anvaka/atree/pull/14](https://github.com/anvaka/atree/pull/14)

<comment><USER14> I prefer people open issues before sending in PRs. I also always open an issue before creating a PR. It's possible the maintainer has different ideas/context I'm not aware of. You just never know. Surprise PRs can be disappointing for both parties if the maintainer decides to turn them down.

<comment><USER13> Oh, that's a really good point!

My approach is mostly shaped by my company's culture (which is definitely not one-size-fits-all): if it's a quick thing to code up, I prefer submitting it as a PR with an [RFC] prefix (I've re-titled my PR to include that), so the maintainer knows I'm not too tied to it.

I'll probably lean towards opening issues before PR's in the future though - thanks!

<comment><USER12> The problem with one-line PRs is that Github forces you to fork the repo first, but I don't want to litter my repository list with forks for one-off contributions.

</comment></comment></comment></comment></comment></comment><comment><USER15> Desmos always has cool stuff:

[https://www.desmos.com/calculator/9czmkyav8o](https://www.desmos.com/calculator/9czmkyav8o)

</comment><comment><USER16> Here is my take on it in ~140 characters of Javascript: [https://www.dwitter.net/d/16973](https://www.dwitter.net/d/16973)

</comment><comment><USER17> a GLSL vertex shader version

[https://www.vertexshaderart.com/art/uDBqerAHTiHEjQMdR](https://www.vertexshaderart.com/art/uDBqerAHTiHEjQMdR)

more of them

[https://www.vertexshaderart.com/art/rBjrdN2CvsneEkgEk](https://www.vertexshaderart.com/art/rBjrdN2CvsneEkgEk)

and yet another Christmas themed one

[https://www.vertexshaderart.com/art/23ezRZjpZK82TqNJr](https://www.vertexshaderart.com/art/23ezRZjpZK82TqNJr)

</comment><comment><USER18> A thread from last year: [https://news.ycombinator.com/item?id=18758290](https://news.ycombinator.com/item?id=18758290)

Discussed at the time: [https://news.ycombinator.com/item?id=6971693](https://news.ycombinator.com/item?id=6971693)

Edit: not implying that this is a dupe—I just mention these links for the curious. On HN, reposts don't count as dupes if a year or so has gone by: [https://news.ycombinator.com/newsfaq.html](https://news.ycombinator.com/newsfaq.html).

</comment><comment><USER19> Why not progressively reduce the angle to the cone's surface to keep the angle to horizontal the same all the way up?

</comment><comment><USER20> I love this place.

</comment><comment><USER21> It's moments like these that I realize I should have perused more math to find my true programming potential. :/ I'll never be the good without it.

<comment><USER2> I think if you find passion that needs math, you'll get your math to solid level too.

I'm personally never was good at math, so I want to see how it looks. That Christmas tree took me probably a week to build, and for someone it is likely a 10-20 minutes project.

Anyway, this curiosity motivates me to learn and build more. Hope it would work for you too!

<comment><USER22> > I think if you find passion that needs math, you'll get your math to solid > level too.

This is an excellent point! There's no surer way _not_ to motivate yourself to learn something than to think "maybe I'll use this one day" (or at least that's how it works for me); there's no surer path to lasting motivation to learn something than thinking that it'll be useful to address my current problem. (And then, once you get started learning it, often you'll find you get so excited that you go far beyond what you actually need–and that's fantastic!)</comment></comment></comment>


Ask HN: What is your hackathon or weekend project software stack? - <AUTHOR> I had a discussion with a co-worker over whether we prefereed to use Ruby/Rails or Node.js for a typical "weekend project" that required a web front end with user authentication, some kind of data store, and maybe a REST API.  This led to a discussion of what frameworks we used as a go-to recipe for starting a new project.
I'd really like to hear the exact language/framework/scaffolding combinations people are using for building quick web projects and testing out start-up ideas.
If met someone today with a brilliant idea that you wanted to launch in 48 hours, what exact tools would you pull out of your tool chest?  Do you start from scratch?  Or do have a go-to web app template you've built yourself or maybe you pull down someone else's scaffolding?  What things have you tried in the past that you wouldn't use again?
I think we can all learn a lot by seeing what everyone else is using to build and launch quickly.  It would be great if you could include links to any specific tools you use that are less familiar to people. <comment><USER2> I came across this hackathon starter project a few weeks ago: [https://github.com/sahat/hackathon- starter](https://github.com/sahat/hackathon-starter)

Have not used it yet, but the stack (node.js, mongodb with mongoose, express) is similar to what I use in my day job so planning to start my next weekend project with it.

<comment><USER3> I've played with it. It's nice. But in my defense, it's literally the only Node framework i've ever touched.

Had to switch out Jade for twig though. Significant whitespace for html templating... _shiver_

<comment><USER4> I've never seen Jade before.

Python + Jade + CoffeeScript + SASS (original syntax) = No more braces evar!

<comment><USER3> I like braces though. And raw html. And I don't think tools should enforce significant whitespace if they compile to languages which don't care about whitespace.

And this makes me horribly, terribly behind the times and now i'll just be in the angry dome...

<comment><USER4> Ha ha, that's what makes me a Pythonista and you not one :)

I like the idea because it (presumably) forces conformant html. The end result that gets sent to the user should be compressed and minified anyhow.

<comment><USER3> It's a fair cop.

</comment></comment></comment></comment></comment></comment><comment><USER5> There was a post a couple weeks ago along the exact lines of this. The guy actually released the framework ish thing he used on github. Its a node pleb stack link: [http://www.rm2kdev.net/2014/02/built-full-application-two- da...](http://www.rm2kdev.net/2014/02/built-full-application-two-days/)

I got to working on something using this but wasn't a fan of a few things so I ripped it apart and created my own from scratch. It was a good learning experience in any case but all I ended up changing was a couple of requires, made the configs a bit cleaner and included https by default. Usually you do that with a nginx proxy but I like to keep things pure and stand alone if possible.

After learning a bit from that I'm now only using it as a rest api back end.

My front end stack is amounting to something like this so far:

\- Angularjs and or node express MVC with mustache

\- Suitcss for the obv

\- Busterjs to test

\- Gulp to build

\- Component.io to manage deps

\- mongodb (its unstructured way is great for weekend projs)

There are a lot of options, and a lot more options the lower you go. I.e PayPal or stripe, express or restify etc etc. Those are mostly per project preferences to me so I didn't bother listing.

I still need something for doc generation needs to be node based or at least hackable to be. If anyone knows anything good let me know. I dont really like what's out there I prefer something highly automated even if its a pain to set up its worth it when it comes to docs.

Speaking of generation again I'd really like to see an api crawler / client lib generator for express. Anyone know of anything?

I also need more easy setup ci options.

Edit, didn't really answer your question: I tend to avoid app templates and generators like yeoman. They never really suit me and my tastes, maybe I should make one? Heh.

</comment><comment><USER6> I use angular/bootstrap/parse.com. use yeoman angular to get everything in place.

I'll then use a s3 bucket as a website when I want to 'go live'. The backend as a service can be a huge time saver for quick projects - immediately you have your datasource+authentication taken care of and can worry about other things.

</comment><comment><USER4> I've ran two hackathons, and I keep turning back to bottle.py + mongodb on Heroku. It's the fastest to spin up and modify by a long stretch.

Give MongoDB as much gruff as you want for whatever reason you're predisposed to hate on it, but it's IDEAL for a hackathon where you just want to get stuff done.

<comment><USER5> Have to agree, mongo is seriously good for spin up as you put it, pretty much zero configuration, define your "database" schema directly in your app as you make your models (at least thats how it works with mongoose.) Can't get much faster than that. How does the python side of things go?

I don't really understand the hate for mongo.. most of the problems people have with it are problems said people would never face with any data store. Its good at what it does. I think it mostly becomes a problem when people try to use it for something they should be using a relational database for.

<comment><USER4> Bottle or Flask are really simple microframeworks. Define your path, define your function, done. There are similar things for other scripting languages like Ruby and Node, but I'm not familiar with them.

</comment></comment></comment><comment><USER3> I have XAMPP for PHP, with starters for Slim Framework and Laravel 4 all set with Twig, Bootstrap and/or the HTML5 boilerplate, also a development install of Wordpress for testing plugins and custom themes. I've also got node.js running now, but I hardly use it yet.

</comment><comment><USER7> I use my own Ruby framework: more capable than Sinatra, less complex than Rails. It's basically Rack, DataMapper, Postgres, an admin UI, and a few reusable bits that I've coded for previous projects (principally user auth and caching).

</comment><comment><USER8> Node.js with Bogart (promise-based framework similar to Express), Redis or Postgres, and Foundation. It helps to have a Yeoman generator specifically for it. yo bogart in any directory and boom, ready to roll :)

</comment><comment><USER9> node.js, primus (for websockets), angular.js and mongodb it's all ready to use in [https://github.com/nherment/node- boilerplate](https://github.com/nherment/node-boilerplate)</comment>


Controlling Itunes With Macruby - <AUTHOR> http://merbist.com/2010/01/17/controlling-itunes-with-macruby/

<comment><USER2> Pretty neat. You need Snow Leopard for 0.5 beta 2 download to work, but apparently you can get it working on leopard if you build from source. Ruby on the llvm with native access to cocoa.. it is pretty neat! One of the gotcha's that I've noticed is that .alloc is not automagically mapped to .new on the framework classes.</comment>


Debunking the 100X GPU vs. CPU myth (PDF) - <AUTHOR> http://portal.acm.org/ft_gateway.cfm?id=1816021&type=pdf&coll=GUIDE&dl=GUIDE&CFID=11111111&CFTOKEN=2222222

<comment><USER2> A couple of notes:

1) the GTX280 is not exactly top of the line anymore, it is now fully two generations behind. The sweet spot cost/performance wise is the GTX295.

2) you can stick 4 top notch cards in a machine, with 2 GPUs each, giving you a net 8 fold increase over the results in the paper, or if you take their 2.5 times figure as a baseline for a 20 fold increase over a regular CPU (if you believe the rest of the claims the paper makes).

3) GPU speedups can not be 'averaged', you either have something that maps well to the GPU or you don't, if you do extreme speedups are possible, if you don't you'll end up spending a large amount of time trying to adapt your problem to the architecture of a GPU, if your time is cheap or of the problem is large enough that your time spent is a small fraction of the total cost this may be worthwhile.

4) So, if you have a problem you need to solve only once and the trade-off is your time vs cpu time then most of the times cpu time will win out, but if the problem is recurring in nature and matches the model well then GPUs are pretty much unbeatable for FLOPS/$ and FLOPS/W (at the moment, and no doubt this will change at some point in the future).

<comment><AUTHOR> Your points are excellent, but number 2 seems a weak: why think of it as a single "machine"? If that's the metric, dual- and quad-processing machines would counter any advantage.

Plus or minus some overclocking, a GTX280 and a Core i7 960 both consume roughly the same number or watts (130 for the processor vs 200 for the card?) and cost roughly the same (at least they did when I bought comparables). So while you can stick (and probably should) stick multiple cards in the same machine, it seems a little silly measure this in terms of multiples of single CPU performance.

NVidia's blog response is interesting, and the some of the comments are actually worth reading: [http://blogs.nvidia.com/ntersect/2010/06/gpus-are- only-up-to...](http://blogs.nvidia.com/ntersect/2010/06/gpus-are-only-up- to-14-times-faster-than-cpus-says-intel.html)

To me, the interesting question here is the degree to which the code has been optimized in each case, and the difficulty of doing so. A while ago there was a competition to attempt to generate SHA1 hash collision: [http://www.engineyard.com/blog/2009/programming-contest- and-...](http://www.engineyard.com/blog/2009/programming-contest-and-the- winners-are/)

The GPU's trounced every other approach. I participated in the contest minimally (running slightly tweaked versions other people's code on both an Nvidia GPU and a Core i7) and I was amazed at how much more efficient the GPU solution was. I don't recall the exact ratios, but 'orders of magnitude' was definitely not an exaggeration.

But that's sort of a contrived example. So what I'd love to see here is a framework that incentivizes each side to come up with their best solution to some real world problem. My instinct is that there are definitely problems for which 100x is realistic. Knowing which problems these are (and aren't) would be a more effective 'debunking' than a one side proclaiming an 'average' result.

<comment><USER2> I think of the GPU as an 'extra', not in place of, so whatever advantage a regular CPU has you always get more bang for the buck by adding one or more GPUs to a machine, assuming your workload is a good match. If not then it's money thrown away.

True that dual and quad processor machines would work even better, but there too it is extra, and especially quad machines are not nearly as cheap as adding GPU cards, CPUs get more expensive quickly as the number of CPUs on the motherboard increases.

Personally I'd like to see research like this come out of different corners than either Nvidia or Intel.

For those jobs that I used GPUs for (image recognition) they outperformed the CPU on the same task better than 50 to 1, the trick is to keep communications down to a minimum and maximize your use of GPU memory. And that's a lot easier said than done, not all of it is intuitive.

</comment></comment></comment><comment><USER3> Forgive me if I take a debunking of GPU performance advantages written up by Intel with a fist sized grain of salt.

<comment><USER4> Thank you. I came over to the comments precisely in order to find out what the author's interests might be.

</comment></comment><comment><USER5> I would say that CUDA is part of their speed problem.

My company has been doing GPU programming for years and we often get 100X-300X+ speedup over the CPU, but we do almost all of our GPU work in shaders. CUDA/OpenCL is much nicer to deal with, since not all problems map nicely to pixel/vertex shaders, but we've tended to have a very difficult time getting CUDA to go from "it's working" to "wow, that's fast". Luckily, in our space most operations map well onto shaders.

</comment><comment><USER6> I saw a talk the other day done by an independent researcher saying a similar thing, comparing a high end Nvidia card to a Intel quad core chip. The speed up was really only 1-2x most of the time and researcher thought maybe 10x could be achieved for some codes but 100x was not acheivable.

<comment><USER7> Yes, 100x _is_ achievable. But only with embarrassingly parallel workloads and when comparing a high-end GPU against a modest dual-core CPU.

For example the AMD HD 5970 can execute exactly 100x more 32-bit integer or floating point operations per second than a dual-core 2.9GHz CPU with 128-bit SSE code.

Embarrassingly parallel workloads such as password hash cracking scale exactly linearly with this 100x difference.

<comment><USER8> In terms of raw FLOPs, the current top ATI card (the $2k FireStream) is 4x the double precision FLOPs of the current top Intel 6-core ($1k).

<comment><USER7> The Opteron 6176 SE provides 38% more DP FLOPS (110.4) than the "current top Intel 6-core" i7-980X (80). So the former reduces the gap even more.

</comment></comment></comment></comment><comment><USER9> Relevant chart here: [http://realworldtech.com/page.cfm?ArticleID=RWT090909050230&...](http://realworldtech.com/page.cfm?ArticleID=RWT090909050230&p=2) ("shows the peformance per watt and performance/mm2 of silicon for various CPUs and GPUs.")</comment>


Jaan Tallinn Co-Founder at Skype and Kazaa Joins Online Hackathon Judge Board - <AUTHOR> https://hack.ether.camp/#/judges? <comment><USER2> Also Meni Rosenfeld who's one of the first people involved with Bitcoin and Bitcoin mining research. Also the founder of the Israeli Bitcoin Association.</comment>


Python decorators they don't tell you about - <AUTHOR> https://github.com/hchasestevens/hchasestevens.github.io/blob/master/notebooks/the-decorators-they-wont-tell-you-about.ipynb <comment><USER2> This notebook should be named "how to abuse decorators". Honestly, there is very little here that you want to use in a real project.

I completely agree in that saying "a decorator is a function that takes a function and returns a function" isn't technically correct since you can do much more than just that; but for readability, maintainability and other real world purposes, you might want to keep to that definition.

<comment><USER3> I disagree. From the end section of "real-world usage examples", there is this library [https://github.com/mrocklin/multipledispatch/](https://github.com/mrocklin/multipledispatch/) that implements "Decorators for registration. It's used in at least one (probably many more) serious open-source project that I know of: GPflow [https://github.com/GPflow/GPflow/blob/master/gpflow/expectat...](https://github.com/GPflow/GPflow/blob/master/gpflow/expectations_quadrature.py#L63) .

"Decorators for preconditions" look pretty neat as well. It's a little sad that the preconditions themselves have to be written inside strings though.

<comment><USER4> > It's a little sad that the preconditions themselves have to be written > inside strings though.

Isn't it possible to pass a lambda instead?

<comment><USER5> Yes. Lambdas in Python are awkward, but you can definitely use either a lambda or a named function.

In fact, you could define a number of useful precondition functions in a single module and use them throughout a project. A couple of higher-order functions could make the post's examples safer and nicer-looking too. For example:

        @precondition(starts_with('The year is '))

where the starts_with precondition is:

        def starts_with(param):
            def test(s):
                return s.startswith(param)
            return test

<comment><USER6> > Lambdas in Python are awkward

Can you elaborate on that, please?

Considering the examples given by the author, I think they would be a better option.

<comment><USER7> Not the OP but I think he was referring to the restrictions python puts on lambda expressions:

\- they can only contain a single expression

\- they cannot contain statements

<comment><USER8> Python has lambdas that have multiple expressions and statements.

They're called functions.

<comment><USER9> Python functions aren't anonymous

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER10> If you're on mobile, view the page as a desktop site in your browser to see the IPython notebook rendered properly. This works on iOS at least.

<comment><USER11> Same in Chrome on Android. Thanks!

</comment></comment><comment><USER12> Consider functools.wraps[1] in your own decorators. This uses functools.update_wrapper to copy the name, docstring, and some other other attributes[2] from the wrapped function to the wrapper.

[1]: [https://docs.python.org/3/library/functools.html#functools.w...](https://docs.python.org/3/library/functools.html#functools.wraps)

[2]: [https://docs.python.org/3/library/functools.html#functools.u...](https://docs.python.org/3/library/functools.html#functools.update_wrapper)

EDIT: s/wrapped/wraps/; tip of the hat to @ramnes

<comment><USER2> Yes! It's functools.wraps*, though. :)

</comment></comment><comment><USER13> URL for mobile: [https://nbviewer.jupyter.org/github/hchasestevens/hchasestev...](https://nbviewer.jupyter.org/github/hchasestevens/hchasestevens.github.io/blob/master/notebooks/the- decorators-they-wont-tell-you-about.ipynb)

</comment><comment><USER14> I've used decorators mainly to retry a function if it throws an exception, like retrying DNS queries multiple times, etc. I've never got a chance to do more with them, but this article gives me an incentive to try more.

<comment><USER15> Yep. I do the exact thing for a lot of network related things (dns lookups, http requests). I use this nifty library: [https://github.com/jd/tenacity](https://github.com/jd/tenacity)

<comment><USER16> Wow, both terrific tips, thanks!

</comment></comment></comment><comment><USER17> My favourite library for writing decorators that "behave nicely" is wrapt – [https://wrapt.readthedocs.io/en/latest/](https://wrapt.readthedocs.io/en/latest/)

There's also a wealth of resource in the docs!

</comment><comment><USER18> Medium to large Django projects were the first times that I began to see the power and usefulness of decorators. The most useful one I've used was a decorator to require certain JSON parameters in a POST and optionally specify a list of possible parameters. Makes the API code logic infinitely simpler, especially if you write some custom middleware to handle / report API errors. The code is clear and declarative, and errors are handled gracefully all in one place.

<comment><USER19> Which is very funny, because you'd get the same without decorators by simply using properly defined RPC protocol instead of ad hoc developed entangled mess that passes as REST.

<comment><USER20> You still have to define the procedures to use with the protocol using language features - like decorators. For example: [http://spyne.io/docs/2.10/reference/decorator.html](http://spyne.io/docs/2.10/reference/decorator.html)

</comment></comment></comment><comment><USER12> functools.lru_cache[1] from the standard library is a decorator that memoizes[2] a function.

[https://github.com/osteele/callgraph/blob/master/examples/ca...](https://github.com/osteele/callgraph/blob/master/examples/callgraph- decorator-examples.ipynb) has some examples of using @lru_cache, together with a decorator (@callgraph) defined in that repo, that helps visualize recursion and memoization.

[1]: [https://docs.python.org/3/library/functools.html#functools.l...](https://docs.python.org/3/library/functools.html#functools.lru_cache)

[2]: [https://en.wikipedia.org/wiki/Memoization](https://en.wikipedia.org/wiki/Memoization)

</comment><comment><USER21> WTH is that call to os.system("rm -rf /") doing there?! Issued a PR.

<comment><USER22> Reading the text around it makes it pretty clear: it's code that shouldn't ever be called.

<comment><USER23> It's still widely inappropriate.

<comment><USER24> It is showing confidence that the author know what he is talking about, because as you can see he ran the code and that part did not run.

<comment><USER25> jupyter notebooks are easy to share and run locally, so it's still inappropriate

<comment><USER26> curl | bash is easy to run locally too, and very few people actually read the code that runs to check for "rm -rf /"-type things. When executing untrusted code from the internet, either you read it or your fate is in the author's hands. No exceptions, not even for beginners getting started in programming via jupyter notebooks.

<comment><USER21> Well, then let's go with the fact that a function called "never_called" is trying to delete all the files on the computer. At best it's a misnomer.

And it is right that the fate is in the author's hands. It's those hands that we are trying to tame.

</comment></comment></comment></comment></comment></comment></comment><comment><USER27> I've been exposed to decorators (starting with Java) and have 'gotten' them and I will proudly admit that I despise decorators and don't think they are great at all.

<comment><USER28> Just hate them? Did they steal yoUr lunch money? Or is there something more specific you hate about them?

<comment><USER27> Mate, you've got some broken images on your homepage.

<comment><USER28> Thank you for the heads up! Will fix when I get home

</comment></comment></comment></comment><comment><USER29> It's all very well writing fancy decorators, but unittesting them, specifically, mocking decorators is trickier.

</comment><comment><USER30> I had fun a little while back abusing decorators to alter the return value of generator functions: [https://sites.google.com/site/bbayles/index/decorator_factor...](https://sites.google.com/site/bbayles/index/decorator_factory)

</comment><comment><USER31> Uploaded to Azure notebooks in case anyone wants to run/play with the code:

[https://notebooks.azure.com/smortaz/libraries/PythonDecorato...](https://notebooks.azure.com/smortaz/libraries/PythonDecorators/tree/notebooks)

Click Clone & Run.

</comment><comment><USER32> one guy made a "pure" decorator that used the ast module to assess the purity (to a certain extent) of a function and allow optimisation on the way

fun

crazy and fun

<comment><USER33> I once wrote a decorator that translated the function to Javascript and spawned a web server, allowing the function to be computed in parallel by multiple browsers: [https://bitbucket.org/robertodealmeida/parallejax](https://bitbucket.org/robertodealmeida/parallejax)

<comment><USER32> cute one

</comment></comment></comment><comment><USER34> Decorators are great. One or two or three. 4 is pushing it. Some people get all carried away though. I saw code recently that had a stack of like 8-10 decorators on top of each function. More decorators than function in every case. Thinking it might be time to re-evaluate basic structure in this case but maybe I just don't get it.

</comment><comment><USER35> > Nothing in x = d(x) necessitates that d is a function - d just has to be > callable!

Python being duck-typed, what's the distinction?

<comment><USER8> "callable" essentially just means you can put a "()" after the name in the code and it works.

You can "call" a class. Doing so allocates an instance of that class (Or calls the __new__ function if one is defined) and returns it, first calling the __init__ function of that class if necessary.

You can also "call" an object if its class has a __call__ function defined.

<comment><USER35> Indeed, but isn't that exactly what "quacking like a function" is?

</comment></comment></comment><comment><USER36> The funny thing is that all of the "useful examples" were functions that took functions and returned functions.

</comment><comment><USER37> Can you make a decorator that references a class instance and has parameters?

<comment><USER38> Yes on the former (works just like you'd expect); to make a decorator take parameters, to do something like:

        @decorator_with_params("Some string")
        def my_function():
            pass

you have to make 'decorator_with_params' a function that returns a _decorator_ ; i.e.

        def decorator_with_params(param):
            def real_decorator(function):
                def inner(*args, **kwargs):
                    print(param)
                    function(*args, **kwargs)
                return inner
            return real_decorator

(You can also do something similar with callable objects, but that's ickier IMO.)

Demo of both (decorator as instance method and decorator with parameters): [https://gist.github.com/jonathonw/dac88b715aca4e4f1b2f513e1f...](https://gist.github.com/jonathonw/dac88b715aca4e4f1b2f513e1feaa102)

<comment><USER39> So just a function that returns a closure? It can be a real pain to read code like this if it's overdone -- I really would need to trust somebody to let them go _meta_ at their discretion.

<comment><USER40> I can't see any reason you can't do something like:

        class MetaDec(args, here):
            ...
            def __call__(self, func):
                # Decorate function here

        def meta_dec(args, here):
            return MetaDec(args, here)

        @meta_dec
        def decorated:
            ...

(apologies for any syntax fails, python is not my best language)

At which point one would imagine you can abstract out the __call__ part and just have a 'decorate' routine on any class designed to work what way or similar.

Whether this is an improvement or not over closures almost certainly depends on the use case, of course.

<comment><USER39> Does the code actually work? Wouldn't you need to create a instance within meta_dec and return the result of the __call__ method. See at first glance I won't think it would work if I didn't know __call__ is a magic method in python. I don't think I'm being overly picky but I found the previous example much easier to read -- since it's a pattern I defaulted to myself before across several different languages. Mixing classes and FP like that doesn't resonate well with me tbh, but yeah you could do it ... but should you?

<comment><USER40> > Does the code actually work?

Given its reliance on '...' and the fact I'm not great at python and typed it straight into the comment ... no. No it doesn't.

> Wouldn't you need to create a instance within meta_dec and return the result > of the __call__ method.

No, like with ES6 parameterised decorators return a function that then gets called with the thing being decorated.

> See at first glance I won't think it would work if I didn't know __call__ is > a magic method in python.

(1) my reply was assuming the context of us both having just read the article, which has an example with __call__

(2) as I said in my original comment, you would abstract this away (and document it), I was sketching out an alternative implementation path to allow you to have an object instead of a closure since you didn't seem to be happy with closures, not offering a complete solution

> Mixing classes and FP like that doesn't resonate well with me tbh, but yeah > you could do it ... but should you?

(3) if you don't like closures _and_ you don't like objects, I'm not sure what other combined function+data abstraction is available in python that you wouldn't also dislike

(4) I'd probably consider doing it if I had a bunch of similar decorators and found the functional approach was starting to groan at the seams - I use objects for 'parameterised bag of functions, possibly with inheritance' quite a lot for that purpose

<comment><USER39> Sorry, must of given off the wrong impression. I'm quite happy with FP in general, I'm just aware it is possible to write some pretty horrendous things. But yeah you are completely right about (4), at some point it doesn't seem like overkill anymore.

<comment><USER40> I was very much trying to find an answer to your

> It can be a real pain to read code like this if it's overdone

wherein (4) is, when things start getting complicated, a way to end up avoiding things turning into closure soup. Also being able to selectively override things with inheritance can really help factor things out and clean things up.

> at some point it doesn't seem like overkill anymore.

Though I suspect "at that point, ask yourself if you're overengineering it and only if you're sure you aren't consider moving to a class" definitely applies :)

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER41> Python decorators are like poor man's method combination.

<comment><USER12> They're a kind of advice [1]. Advice was indeed subsumed by CLOS method combination, but existed prior to that and has a life of its own, for example in Aspect Oriented Programming.

[1]: [https://en.wikipedia.org/wiki/Advice_(programming)](https://en.wikipedia.org/wiki/Advice_\(programming\))

[2]: [https://en.wikipedia.org/wiki/Aspect- oriented_programming](https://en.wikipedia.org/wiki/Aspect- oriented_programming)

</comment></comment><comment><USER42> To be honest, decorators were always, idk, I felt like there was something off about them.

<comment><USER43> > To be honest, decorators were always, idk, I felt like there was something > off about them.

I think they're one of those things you don't need to use unless you _need_ to use them...though, honestly, you probably don't ever _need_ to use them unlike metaclasses where sometimes they are the only way to do something in a reasonable manner.

<comment><USER44> > _you probably don 't ever need to use them_

By their definition, you don't ever need to use them. They're just a convenient syntactic sugar.

      @foo
      def bar():
          ...

is, as far as I know, exactly equivalent to

      def bar():
          ...
      bar = foo(bar)</comment></comment></comment>


Python for Fun - <AUTHOR> http://openbookproject.net/py4fun/index.html

<comment><USER2> Lisp interpreter written in python: <http://openbookproject.net//py4fun/lisp/lisp.py>

Several projects seem highly inspired by SICP (which is cool).</comment>


Koalas 'Functionally Extinct' After Australia Fires Destroy 80% of Their Habitat - <AUTHOR> https://www.forbes.com/sites/trevornace/2019/11/23/koalas-functionally-extinct-after-australia-bushfires-destroy-80-of-their-habitat/ <comment><USER2> "Following the initial declaration of 'functional extinction' in May, Christine Adams-Hosking, a conservationist at the University of Queensland, penned an article for The Conversation more accurately outlining the fate of the koala in Australia. In it, Adams-Hosking made it clear the functional extinction tag was one likely applied with a little too much haste. In a study conducted in 2016, a collaboration of researchers attempted to quantify how many koalas were left, but it's a complex game."

[https://www.cnet.com/news/koalas-are-not-functionally- extinc...](https://www.cnet.com/news/koalas-are-not-functionally-extinct-but- they-need-our-help/)

</comment><comment><USER3> forbes is shit, the headline is a lie.

[https://www.cnet.com/news/koalas-are-not-functionally- extinc...](https://www.cnet.com/news/koalas-are-not-functionally-extinct-but- they-need-our-help/)

<comment><USER4> Not only Forbes, apparently.

[https://twitter.com/JacquelynGill/status/1198437407475015682...](https://twitter.com/JacquelynGill/status/1198437407475015682?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1198437407475015682&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Fkoalas- are-not-functionally-extinct-but-they-need-our-help%2F)

(from the parent's link)

</comment></comment><comment><USER5> I hate to be the person saying something like "koalas are only in _terrible_ trouble, not _awful_ trouble", because it's clear that the issues are serious (not to mention the over-arching issue of climate change). But in an article linked from this one there's this quote:

"The number given by the Australian Koala Foundation is much lower than the most recent academic estimates, but experts agree that koala numbers in many places are in steep decline."

So the line about "experts" in the Forbes article are the Australian Koala Foundation, not academics who study koalas.

As I say, I'm reluctant to bring this up because it may sound like I'm deliberately trying to diminish the importance of habitat destruction on koalas, which is clearly serious. But the headline for me feels like Forbes chose the most emotive possible interpretation to gain some clicks, rather than it being a sober analysis of the (clearly serious) situation, and therefore I'm doubtful of the "functionally extinct" part of this.

The reason I'm quibbling is that if this claim is over-stated, it's going to lead to people thinking "well, last time they said functionally extinct it wasn't true, so it probably is this time," and will make these kinds of claims easier to dismiss in the future.

<comment><USER6> It's also worth noticing that the author of the Forbes thing is a "Forbes contributor" i.e. a person using the Forbes blogging platform, not a Forbes journalist. Serious topics deserve better journalism than this article.

</comment></comment><comment><USER7> Although 1000 koalas are believed to have been killed in these recent fires (from the article), it doesn't look like they are "functionally extinct" [1]. Also, it seems like that particular claim was made earlier the year as well (before the presumed most recent fires). I don't know what to say about the "80% of their habitat" claim.

In any case, as many have lamented before me, it's a pity that we keep wanting poster boy animals rather than just general, sanitory debate around nature conservation.

[1] [https://www.newscientist.com/article/2203655-no-koalas- are-n...](https://www.newscientist.com/article/2203655-no-koalas-are-not- functionally-extinct-but-they-are-in-trouble/)

<comment><AUTHOR> > we keep wanting poster boy animals rather than just general, sanitory debate > around nature conservation.

Same here, but I also can't disagree because if we don't get the population a little enraged and hyped up about it then there will be no pressure on the politicians. At least this is the case in the US where oil/gas/mining lobbyists continue to have protected lands changed to unprotected so they can rape and desecrate it for profits.

<comment><USER8> > if we don't get the population a little enraged and hyped up

I disagree - people just become numb and tune it all out. Plus, the opposite side then just point out the exaggerations to their own benefit.

<comment><USER9> Bingo, outsize panic serves politicians, but rarely serves causes in the long run.

</comment></comment></comment></comment><comment><USER10> There will come a time when we can only view the most interesting wildlife that was common a hundred years ago only in pictures and movies. Super sad. As a kid I had an encyclopedia of all the animals, not a kids book but a pretty serious book with a page per species. I wonder how many of those that were still around back then (1975) are gone today. Probably not a happy answer to that question.

Koala's still stand a chance of survival if humanity wishes it to be so.

<comment><USER11> Was it, perchance, the Larousse? I loved that book.

<comment><USER10> Interesting, never thought of looking it up, this was the book:

[https://www.boekwinkeltjes.nl/b/103530821/De-grote- encyclope...](https://www.boekwinkeltjes.nl/b/103530821/De-grote-encyclopedie- van-het/)

For sale on the local ebay equivalent for 1,50 euros... a steal at that price:

[https://www.marktplaats.nl/a/boeken/dieren-en- huisdieren/m14...](https://www.marktplaats.nl/a/boeken/dieren-en- huisdieren/m1458743914-dierenrijk-stanek-grote-encyclopedie-van-het- dierenrijk-1963.html)

The ad has some of the contents in it, most of the images were b&w with only very few pages in color. Still, I loved that book and tried real hard to learn it by heart.

<comment><USER11> Similar in scale and tone to the Larousse, certainly. Every kid should have one in their life.

</comment></comment></comment></comment><comment><USER12> Doubly tough that the eucalyptus tree is an excellent fuel source for wildfires (hence there's been an extensive removal program by northern California municipalities over the last decade)

<comment><AUTHOR> That's interesting, is it because the sap acts as a flammable gel?

<comment><USER13> from [https://en.wikipedia.org/wiki/Eucalyptus#Adaptation_to_fire](https://en.wikipedia.org/wiki/Eucalyptus#Adaptation_to_fire):

"Eucalyptus oil is highly flammable; ignited trees have been known to explode. Bushfires can travel easily through the oil-rich air of the tree crowns...

...In seasonally dry climates oaks are often fire-resistant, particularly in open grasslands, as a grass fire is insufficient to ignite the scattered trees. In contrast, a eucalyptus forest tends to promote fire because of the volatile and highly combustible oils produced by the leaves, as well as the production of large amounts of litter high in phenolics, preventing its breakdown by fungi and thus accumulating as large amounts of dry, combustible fuel."

So yes, part of it is that it secretes oils that are highly flammable. Another part is that it tends to accumulate dead leaves etc at the base, which aren't broken down as fast as that of most trees.

The Eucalyptus has evolved to expect periodic fires - it's flammable because stoking fires is adventageous to it. The problem is that now, due to climate change, the fires are more frequent and more intense, and because habitats are so small, there's nowhere else for the koalas to go when one part of the forest burns.

</comment></comment></comment><comment><USER14> This is really sad to hear. I hope that we're capable of restoring their habitat to a reasonable extent, and that the natural population subsequently rises up again.

</comment><comment><USER15> I thought koalas were a borderline nuisance species...far more than 1000 koalas in Australia. Maybe less than 1000 outside Australia. Not sure how accurate this headline/story is.

<comment><USER16> There seems to be some confusion between a _population_ becoming extinct and a whole _species_ becoming extinct. More information here. [1]

[1] [https://theconversation.com/a-report-claims-koalas-are- funct...](https://theconversation.com/a-report-claims-koalas-are-functionally- extinct-but-what-does-that-mean-116665)

<comment><USER17> Or perhaps the title of this article is intentionally ambiguous to make people click.</comment></comment></comment>


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Comcast to Unveil Cellular Plans in Challenge to Verizon, AT&T - <AUTHOR> https://www.wsj.com/articles/comcast-jumps-into-wireless-wars-1491471003 <comment><USER2> I hate Comcast. Haven't used them in many years, but seemingly every month I read about something shady they have done to their customers.

I seriously question how many Comcast customers will opt to use any more services than they absolutely have to from an abusive cable monopoly. Maybe I am missing something here?

<comment><USER3> Yeah, I mean, I do choose Comcast for home internet, because the other providers in my area can't provide the performance I want.

...But the last thing I want is to do _more_ business with them.</comment></comment>