How American Airlines is utterly terrible at customer service. - <AUTHOR> http://kylewritescode.com/post/3573171406/why-american-airlines-is-the-epitome-of-terrible

<comment><USER2> Tips from a frequent traveller:

1) I consider a $5 tip to the curbside check in guy a form of flight ticket insurance.

2) Federal regulations mean they owe you when getting involuntarily bumped off flights, and the amount of actual USD compensation increases with the amount of time you wait. (This assumes they believe your "I was on time" story.)

3) When dealing with large bureaucracies, document document document. Conversations held verbally _didn't happen_. Do you have a notebook? If not, go buy a notebook from the gift shop right now. Get people's names and either badge or desk number (it's an airport, they all wear them prominently) every time you talk to them, and write down what they tell you.

4) I can explain at length why your priority is that low on the waitlist queue, but it boils down to "AA could piss off an entire conference worth of you and it still wouldn't cost more than losing one high-priority customer like a twice-weekly business traveller."

</comment><comment><USER3> In other news, the sky is in fact blue. Of course airline customer service sucks.

The secret to dealing with any airline exception is not to run for the ticket counters with the mob -- call the 1-800 number immediately. The folks on the phone can usually do the same thing as someone at the counter, plus you don't have to stand in line.

</comment><comment><USER4> Call your credit card company. They at least care if they lose your business. Have the flight payment refunded back to you and buy a new ticket. Then you won't be in standby anymore.

</comment><comment><USER5> There is no "why" in this article; it is merely about the how.

<comment><AUTHOR> Good point; updated.

</comment></comment><comment><USER6> I find it interesting how many companies I am in a bad relationship with. We never break up, it's just loveless or worse. Sometimes, it's simply too difficult to avoid using some companies. I wouldn't pick American, but I would pick United, AT&T and every fast food chain that operates on the Jersey Turnpike. A monopoly is a terrible thing...not to have.

On the other hand, I happily pay healthy margins to Apple and Amex.

<comment><USER7> ...and you have to pay those margins, in order to get the kind of customer service they provide. However, most people actually don't want better customer service: they want cheaper prices, which leads to competition for lower margins. If you want better service, you need to convince 99% of people to not purchase plane tickets from websites that sort by price (which, incidentally, is also how most people buy telephone service and even the food they eat). I mean, even hipmunk, with its "sort by agony" feature, still is heavily biased towards cheaper flights.

<comment><USER8> We're working toward an agony sort that has all of those subtleties baked into it, even weighted depending on how important they are to you. e.g., I'm quite price insensitive when it comes to wireless + power on my frequent NY<->SF route -- if you can keep me online and powered up for the whole flight, I'll pay for it.

Once we can take into consideration, say, subjective reviews of airlines, routes, etc, things get even more interesting.

Thanks for hipmunking in the meantime, though!

</comment></comment></comment><comment><USER9> Wow. I missed a Delta flight in SF (that while I'll blame the PA system for anyone who listens, was entirely my own fault), and I ended up first on the standby list. I always got the impression agents put people who miss their flights pretty high on the priority list, as opposed to people who just feel like going standby.

Weird that treatment would be so different across airlines.

<comment><USER10> It depends. Airlines distinguish on their waitlists between those who've been inconvenienced entirely outside their control (aircraft mechanical delay even weather) vs. those who've missed their flights because they were late. Sounds like you got lucky and were listed as the former. Sounds like the blog author was the former but was classified as the latter. Neither mis-classification is rare from what I've seen as a very frequent traveler.

</comment></comment><comment><USER11> Idea: put some kind of link to American Airlines website/customer service in your website, so they can see your post as source of web traffic? They are probably "monitoring their brand," but still...

<comment><USER12> Not sure someone will click the link while reading the story</comment></comment>


Securing Your Digital Life Like a Normal Person - <AUTHOR> https://medium.com/@mshelton/securing-your-digital-life-like-a-normal-person-a-hasty-and-incomplete-guide-56437f127425 <comment><AUTHOR> This seems like a pretty comprehensive list of the things that don't require significant configuration, and that don't trade off between comfort and security.

Sadly, email encryption isn't yet on this list. Nor is a near-zero- configuration encrypted backup solution (though that's as much about having good backups as about security).</comment>


A Large Scale Study of Programming Languages and Code Quality in GitHub [pdf] - <AUTHOR> http://macbeth.cs.ucdavis.edu/lang_study.pdf <comment><USER2> "RQ1. Are some languages more defect prone than others" is misleading.

It shows TypeScript having an coef of −0.43, Clojure of -0.29, Scala at -0.28, and Haskell at -0.23 and shows a small amount of standard error for each. That ignores a few things: 1. in Table 2, the amount of data analyzed for each is much different than some of the others, and 2. if some projects are newer or don't have as much activity, they will have fewer issues raised. It's a bad idea to equate that in any way to code quality.

</comment><comment><USER3> Skimming the document in find that in page 3 they have categorized the languages by paradigm in a very weird way.

They list 3 paradigms: procedural, scripting and functional.

First, scripting is not a programming paradigm. The main difference is that compilation is not an explicit step. But even those, some of the languages (Python!) are compiled.

Then, in the Procedural category they have C and Go, but then add C++, C#, Objective-C and Java which are not procedural but OO!!!

The categorization seems completely arbitrary and wrong!

<comment><USER4> C++,C#, Objective-C and Java are all procedural languages. This has little to do with whether they are object oriented or not. That said, it would have been interesting to see whether object oriented features of languages have an effect on software quality.

</comment></comment><comment><USER5> Python and Ruby come out with quite opposite results. There is absolutely no reason why those languages, on their own, should lead to wildly different error rates. Both dynamically typed, general purpose, very equivalent languages. So if this study seems intuitively like a fools-errand, that would be your smoking gun.

The study admits the effects are small. The one clear conclusion is an obvious one:

"Result 4: Defect types are strongly associated with languages; Some defect type like memory error, concurrency errors also depend on language primitives. Language matters more for specific categories than it does for defects overall."

Does Clojure have an inherently lower defect rate than C++? It's arguably an interesting question to ask, but looking at the Python and Ruby results makes it clear, to my anyway, that we'll have to stick to arguing about it over beers, rather than finding the answer in data.

<comment><USER4> The Ruby ecosystem has very strong emphasis on tests and test driven development. Perhaps bugs in Ruby simply often are fixed before they're committed because the test suites have better coverage.

Also I think Ruby developers are more likely to be professional (as in paid and educated to be programmers), whereas python developers might (slightly more) often be mathematicians, scientists or sysadmins.

As is noted in the paper, all other factors that were controlled for were strongly dominant. That means who you are and what you are doing is much more important than what language you do it in.

</comment></comment><comment><USER6> Came up with some similar results a couple months ago. I looked at it from just bugs per commit, but I also have some cool charts! [http://deliberate- software.com/safety-rank-part-2/](http://deliberate-software.com/safety-rank- part-2/)

</comment><comment><USER7> Why does Go do so bad with concurrency errors, when it's supposed to be a darling at concurrency.

<comment><USER8> It probably has something to do with concurrency being common in Go code. The primary implementations of Ruby and Python (for example) have almost no meaningful form of concurrency. That means most Ruby and Python apps have no concurrency, thus no concurrency bugs.

</comment></comment><comment><USER9> Seems to fall right in line with expectations.</comment>


Your Company Culture Sucks, and it's All Your Boss's Fault - <AUTHOR> http://technori.com/2012/12/2849-your-company-culture-sucks-and-its-all-your-bosses-fault/

<comment><USER2> There's no shortage of life-sucking ways a bad fit can ruin you. Unfortunately, it can be rather subtle, a la the metaphor of putting a live frog in a pot and bringing it to boil.

<comment><AUTHOR> agreed. Sometimes it takes you a long time to realize it too. Other times it's right in your face.</comment></comment>


Introducing 'waves': a Common Lisp audio synthesizer - <AUTHOR> <comment><USER2> It's so magical and lispy it doesn't exist

<comment><AUTHOR> Sorry about that, must have been a copy paste error; here's the real link:

[http://busfactor1.ca/kruhft](http://busfactor1.ca/kruhft)

</comment></comment><comment><USER3> There's is no link.

<comment><AUTHOR> [http://busfactor1.ca/kruhft](http://busfactor1.ca/kruhft)</comment></comment>


Math Overflow users resolve PhD thesis crisis - <AUTHOR> https://mathoverflow.net/questions/366765/issue-update-in-graph-theory-different-definitions-of-edge-crossing-numbers <comment><USER2> This reminds me of my Ph.D. crisis. (which I'm sure many former grad students can relate to)

I was in my 6th year. All my friends had graduated, and my stipend had run out. I was 2 weeks away from submission and discovered that one of my assumptions was wrong, which potentially distorted/invalidated all my studies -- to fix these studies would have potentially delayed submission for months. It was a very subtle assumption violation (and it wasn't even that wrong) and my committee probably wouldn't even have noticed. I was tempted to sweep it under the carpet and not let it keep me from graduating.

But I knew it was wrong. I felt that if I sacrificed my integrity then, the moral failure would mark me for life. No one would know -- but I would know. So I decided to fix the issue, re-do the studies and live with the reality that I would have to delay my defense.

Turns out when you're desperate -- and many grad students can attest to this -- a resourcefulness that you never thought you had kicks in ("where were you during all my years of grad school?"). I don't remember how, but I somehow managed to wrangle new studies out in 3 days (which would have previously taken me months). I made the deadline in the end.

The lesson I learned was that committing to doing the right thing has its costs, but in some cases it also forces one to explore attacks never previously considered. Asking on MathOverflow is one such attack.

<comment><USER3> There's another (slightly kinder) version of this:

When people go to grad school, then during their studentship get married and have a kid -- suddenly their productivity goes up dramatically and output per time increases by many factors. What happened?

It turns out when you have self-motivating reasons to get out (and a target on your head from your spouse to earn some money for godssake), you find ways to focus on what's important and drop the rest.

No more idling away for hours on silly ideas that don't get you closer to handing in your thesis. No more trying random libraries that get your code to run 2% faster. No more goofing around after 6pm with other students just because you have the time -- you have to get home and be a breadwinner for your family. You have to get shit done.

You start to ask, "even if I don't know exactly what the thesis will say, how should it be organized and what _kinds_ of conclusions will make up the writing? And what experiments do I need to fill in those charts/paragraphs, and _no more_?" What's the minimum I need to do to get out of here? Not, "What amazing interesting thing could I explore?"

Limits and constraints sometimes free the mind dramatically. The side effect is maybe you don't get to explore ideas that go nowhere, but that's a discussion about the purpose of the PhD and for another topic I guess.

(And sometimes, if you think, well I don't have a kid, so what's the rush? Well, someday you might have a spouse, a kid, and every day of time you left in grad school is a day for your future self -- and family -- and $$ -- left behind in time. Work to free your future self... now, while you have the time.)

<comment><USER4> Hmm this is different than my experience when my co workers had kids. Usually their productivity dropped due to being sleep deprived and not having the time on nights and weekends to come up to speed on any new technology.

Not that I minded, just saying that time constraints and sleep deprivation seemed to have the effect you'd except from them.

<comment><USER5> > Usually their productivity dropped due to being sleep deprived

High levels of sleep deprivation is only common for the first few months.

> not having the time on nights and weekends to come up to speed on any new > technology.

This tends to be a problem on teams that don't properly evaluate costs of new technology and so churn like crazy for very minor productivity increases.

</comment></comment></comment></comment><comment><USER6> A neat comment on the accepted answer:

> From OP's point of view this could be viewed as glass half-full rather than > glass half-empty. Their dissertation results hold unequivocally on the > sphere and might hold on the torus, though it is an open problem if they do. > It is certainly legitimate to study what follows from a given conjecture > being true. It could even be spun as a feature rather than a bug of the > dissertation. If the results in fact fail on the torus then you know that > the conjecture must be false. Potentially, it could open up a fruitful > avenue of attack.

Kind of reminds me of Terence Tao's post on what solving big problems looks like: [https://terrytao.wordpress.com/career-advice/be-sceptical- of...](https://terrytao.wordpress.com/career-advice/be-sceptical-of-your-own- work/)

<comment><USER7> When Terence Tao writes stuff like this, I'm always very happy that I got to experience the Moore-method for learning math (at UT Austin). A group of us would be dumped into a class with a common topic and we'd just have to _prove_ things (topology, algebra, analysis) ... on the blackboard, in front of everyone. The best work we did was when something started going wrong and then we'd all start arguing about the proof, building count-conjectures on the fly and riffing on the math. The worst work was when someone went and found a proof _ahead of time_ and just showed the answer. There's so much to learning where the sharp bits of math are; proofs are the razor-thin path through the briar patch.

It was only later that I found out that history, the study of art & literature, and philosophy can all teach you the same thing. The important part is that you're interested in the topic.

<comment><USER8> > > There's so much to learning where the sharp bits of math are; proofs are > the razor-thin path through the briar patch.

As a student representative for my undergraduate mathematics course, I got really pissed off at lecturers for exactly this reason: they'd write out a perfect correct proof on the whiteboard, but wouldn't explain where it had come from or how people had arrived at the solution. We were left to figure that out on our own.

They then complained that students were rote-learning for exams, rather than coming to a full understanding of the material. I'm not sure what they were expecting, given that that's exactly how they were teaching it.

<comment><USER9> My discrete mathematics professor was like that. He would regurgitate a proof onto the whiteboard. Then he'd do it a few more times with proofs of other things.

He has an identical twin brother, who is also a math professor at the same college. The regular professor was out for a day, and his brother came in to teach the class. His teaching style was completely different. "Ok, we need to prove X. Where should we start?" and would sit on the table and look at us with an inquisitive look on his face. Then learning happened.

Everyone's mind was blown. Most people didn't realize it was a different person. Then on Thursday it was back to same-old same-old.

I still don't know shit about discrete math.

<comment><USER10> I am not getting anywhere with the latter approach when TAing

I ask them such a question, and then wait for 15 minutes, and no one says anything.

</comment></comment></comment></comment></comment><comment><USER11> The walled garden sweet spot

Stack overflow and it's cousin sites have many serendipities like this - and I happily conjecture this happens more here than facebook or twitter.

I think the reason is that despite being a walled garden (ie proprietary) it still has a promise to open up the content and makes effort to moderate and grow the community - in other words what they are really selling is not the SEO but the sweet spot between "anyone posts anything" of an "ideal" internet where no rentiers exist but no one can find anyone else, and the much more corporate hand of Facebook.

I am not sure reddit exists in this sweet spot either - mostly because there is just sooo much reddit.

<comment><USER12> A couple relevant bits of info about MathOverflow:

\- The site is operated by Stack Overflow/Exchange, but is _owned_ by MathOverflow, Inc a non-profit corporation[0]. As such, it retains the right to exist independently of the Stack Overflow company - to my knowledge, it is the only public Stack Exchange site for which this is true.

\- Like all public Stack Exchange sites, authors retain ownership of their work, which is published under a CC-BY-SA license. Regular archives are uploaded to Archive.org and can be obtained there or via Bittorrent[1]

In short, not a walled garden, and not Stack Overflow's garden.

[0]: [https://meta.mathoverflow.net/questions/969/who-owns- mathove...](https://meta.mathoverflow.net/questions/969/who-owns-mathoverflow)

[1]: [https://archive.org/details/stackexchange](https://archive.org/details/stackexchange)

<comment><USER11> Re: MathOverflow Inc - I had not only not heard of this, but never even considered it was possible :-)

Yes, I think I am wrong to use the term walled garden, but it's hard to think of something else.

In a "platonic ideal" of the internet everyone would have their own internet connection, and a server and say post their own interesting queries and somehow others would find and answer them.

Perhaps search was assumed to solve it all then.

But the universe is much more "clumpy" than that so people will gather around certain locations, in nature they are natural oasis.

Perhaps we should drop the walled garden idea - gardens, walled or otherwise need tending and upkeep and that passed the ability of one or two people to do in their spare time somewhere around 1991 on usenet.

Tending a garden is a costly affair.

I think perhaps walled city might be a better term? It implies the "never leaving" which is what facebook seems to aspire to.

perhaps a better analogy is "chargeable car parking". :-)

<comment><USER12> This is yet another one of those situations where the use of a dying metaphor[0] hurts communication; you wall up a garden to protect what is inside from the harsh conditions outside: wind, cold, vermin... The implication is that the people in the garden are delicate flowers who would be destroyed by the conditions on The Greater Internet if they were to be exposed.

The antonym to the walled garden is the open garden or field, with hardy plants able to withstand and even thrive in the local atmosphere. They're still _cultivated_ \- weeded, fertilized - but there's no need to create a microclimate to just to accommodate them.

In this context, Facebook does make some effort toward walling off their gardens, but... As you note, Facebook's primary goal isn't protecting it's _dominating_ \- Facebook is just as happy to own major portions of the 'Net in pursuit of this goal, and more than a little reluctant to provide any real protection beyond what is absolutely necessary.

Beyond that... We all garden. From little personal websites and blogs, to big community gardens[1] like Wikipedia, Reddit, Stack Overflow, and even Hacker News. We plant, we harvest, we tend these plots, alone or together, but make little effort to isolate them from the larger world - indeed, we generally recognize that the strength of the Web is based on its interconnections, its inherent ability to draw together different sources of information.

[0]: [https://www.orwell.ru/library/essays/politics/english/e_poli...](https://www.orwell.ru/library/essays/politics/english/e_polit)

[1]: [https://meta.stackexchange.com/questions/349513/feedback- for...](https://meta.stackexchange.com/questions/349513/feedback-for-the-loop- june-2020-defining-the-stack-community)

<comment><USER11> Interesting - my understanding of the walled garden was the Omar Khayyam style of a luscious oasis walled off to allow only a few people to enjoy it whilst keeping most out (the implication that you had to pay to be one of the few).

Neither definition actually makes much sense when talking about incompatible protocols.

<comment><USER13> One of the major difference when you think of any concrete items like flower, gardens is that they are private goods. Public goods especially information, laws of physics, idea, mathematics etc. are hard to create but no costs to consume. Hence, the walled garden is not about keeping most people out of view i.e. Wall Street J etc. but keeping the noise from the creation so there is a point for the OP to post his question in a panic. Public goods like F=ma is very hard to be created and what motivation to create one is a big question. This is especially if it is networked public goods. And some public goods are useful to one or one group but not the others. That is the fundamental problem here.

Guess the one above this poster has right that the analogy is not totally right. Still if one assume the flower can be viewed a trillion time but the question is creation, walled garden is a good metaphor.

<comment><USER11> The first usage I remember of walled garden in an online sense was about AOL and their refusal to use common internet protocols - you literally could not email from outside AOL and if I remember not view websites outside AOL. There was a wall around their garden. IIRC it became a common description in tech columns of papers.

I still see the walled garden analogy to be more useful

If people are confusing their definition of a metaphor and mine (I don't think Orwell mentioned that but maybe it's low down the list of stylistic errors) then that can cause problems. But I struggle to see how Facebook / twitter "protects" creators from the harsh winds of the outside.

<comment><USER12> This is where the "dying metaphor" thing comes into play: AOL was a walled garden in the sense that I outlined - like so many other early online services (and BBSs), it had walls to protect its members. That was the original sense of the metaphor.

But... That sense is dying; it is a poor metaphor _because_ few people actually build real-world walled gardens[0][1] for that purpose; the metaphor has no currency, and thus the meaning shifts. Now it is just as frequently used to describe any sort of system which restricts the flow of people OR of information, in or out. So while Instagram might be considered a "walled garden" in the original sense (no outbound links on posts), it may ALSO be considered a "walled garden" in the sense that it restricts inbound access for non-members, or even in the sense that it forces certain onerous licensing terms on contributors. In this manner, the metaphor becomes problematic, as what one intends to convey is not necessarily the meaning which is understood by others. If/when the metaphor dies entirely, becoming an idiomatic way of saying "not completely open", this problem disappears - no one will attempt to relate people to plants, or content to flowers.

With this in mind, I suspect your original intent was focused on the "garden" aspect: that the value MO provides comes from imposing a structure and certain expectations which facilitate productive interactions like this, with the "sweet spot" being that it remains _open enough_ for the rest of us to benefit from the outcome of those interactions.

[0]: [https://solar.lowtechmagazine.com/2015/12/fruit-walls- urban-...](https://solar.lowtechmagazine.com/2015/12/fruit-walls-urban- farming.html)

[1]: [https://news.ycombinator.com/item?id=22395292](https://news.ycombinator.com/item?id=22395292)

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER14> As far as notational clusterfucks go, crossing numbers (along with the three standard definitions of a ring) are one of the best-known ones to still be biting people on a regular basis. ("Positive" and "natural number" are sufficiently well-known that people are careful.) But imagine how it felt to do group theory back when "group" could mean any of "abstract group", "subgroup of GL(n)", "finite group", "monoid", "semigroup" and combinations thereof.

<comment><USER15> The simplest gotcha I know is: is f(x) = 1/x piece-wise continuous?. This is calculus 1 level material and yet author's disagree significantly on this point, sometimes without specifying it! Some say yes, others would require f to have finite left and right limits at every point. This mattered for a point of my thesis and my advisor was very unhappy with me calling these function piece-wise continuous.

<comment><USER14> I thought this was only an issue in K-12, as anyone in research math considers the domain and the target to be part of a function, and then the problem disappears: The function R \ {0} -> R, x |-> 1/x is not just piecewise continuous but continuous on-the-nose. The function R -> R, x |-> 1/x doesn't exist. The function R |-> some completion of R, x |-> 1/x is continuous or not depending on which completion you choose (the one with two infinities or the projective line).

But I do recall a similar confusion happening with "piecewise linear" (the question is whether the pieces have to fit together).

<comment><USER15> No you've missed the distinction. In all cases the domain and range are R (you can fill in a value at 0, it doesn't matter which). See the MathWorld page which leaves the definition intentionally ambiguous:

"A function or curve is piecewise continuous if it is continuous on all but a finite number of points at which certain matching conditions are _sometimes_ required."

Emphasis added.

[https://mathworld.wolfram.com/PiecewiseContinuous.html](https://mathworld.wolfram.com/PiecewiseContinuous.html)

<comment><USER14> I don't get this. If you require f to be piecewise continuous outside of a finite set of points _and_ to satisfy left limit = right limit at each of these points, then you just have a continuous function. Why another word for it?

<comment><USER15> The left and right limits are required to exist (and finite), but not necessarily to be equal to each other. So f(x) = 1/x and sin(1/x) are out but x/abs(x) is not.

</comment></comment></comment></comment></comment></comment><comment><USER16> OP is incredibly fortunate. Or maybe mathoverflow is that active/supportive.

As a STEM grad student (not in math), I had more than a couple such moments of crises, when I posted my questions on various stackexchange websites. I got either useless replies, or no replies.

<comment><USER17> Mathoverflow is different from most of the other SE sites in that it's only for research level questions. There is a separate site, math.stackexchange, for other math-related questions.

</comment></comment><comment><USER3> I have to say also that this type of crisis is not surprising (unfortunately) for math, or similar highly theoretical, _loner_ fields. I can guess that the student asking the question is not being very open with his/her advisor, has worked and struggled for long hours alone, thinking they have to solve it on their own, and is not super communicative and checking in about important aspects of the thesis. Because he/she thinks it has to be a surprise "breakthrough" result -- a heavy obligation of the field's expectations.

No responsible advisor would let the work get to such a state, so late in the game. Major fault of the advisor too, here.

<comment><USER18> Advisors are also very much at fault, not just students.

The last year of my PhD I ended up being pretty much alone because my advisor had changed research topics a year before and therefore was not interested nor up to date, so any of her inputs were not very useful.

A couple friends of mine also struggled with their advisor because he actively avoided communication for some reason. I guess he had a personal or health issue.

So even on good faith, advisors can end up making students life quite stressful for one reason or another

</comment></comment><comment><USER19> I was contacted by someone in a PhD thesis crisis who wanted me to provide speech samples they were apparently missing. The thesis was due imminently.

As far as I could tell, the analysis was already done -- but my samples were needed for some other reason. I was kind of bemused by the idea that the analysis would be invalid with nothing behind it, but valid with unrelated data behind it.

</comment><comment><USER20> My insight was an eng. student whose novel outcome of a maths model in Fortran on a mainframe depended on his not understanding what uninitialised arrays were. This was in the 80s.

There was no interesting novel outcome: he was random-sampling prior states of memory.

I felt very bad for him, it was mid-stage. I didn't hear how he resolved it.

The other side of this is the crisis which only emerges in the viva. I was working in Leeds uni in the 80s and overheard an external discussing a case he had: it was obvious the results were fraud. They made the student and his supervisor to the sums in the room, on the blackboard. He didn't get his thesis.

</comment><comment><USER10> I was in a PhD crisis, but I did not post it anywhere. Not sure if it is allowed to ask for outside help.

Although now I have finished the thesis without that part (it should have become an additional chapter). Perhaps I should post it around (although that might spoil it for a paper)

Consider n polynomial equations in variables x_1, .., x_n, with constants a_1,..,a_n, b_1,..,b_n, c_1,...,c_n:

         p_1 := a_1 x_1 x_2 + b_1 x_1 + c_1 x_2 + d_1 = 0
         ...
         p_{n-1} := a_{n-1} x_{n-1} x_n + b_{n-1} x_{n-1} + c_{n-1} x_n + d_n = 0
         p_n     :=   a_{n} x_{n} x_1 + b_{n} x_{n} + c_{n} x_1 + d_n = 0

Under which circumstances exists a (unique) solution for x_1,..,x_n in terms of the constants?

I have found a recursive approach that results in a quadratic equation, containing only a single variable x_i (and the constants). (It is too much for a comment, here is a PDF: [http://benibela.de/tmp/quadratic-equations- recursion.pdf](http://benibela.de/tmp/quadratic-equations-recursion.pdf) )

For example for n = 2, it is very simple: x^2_1 (a_2 b_1 - a_1 c_2) + x_1 (a_2 d_1 + b_2 b_1 - a_1 d_2 - c_1 c_2) + b_2 d_1 - c_1 d_2

This gives 2 solution. But I do not know what happens if the terms cancel each other out. Like if a_2 b_1 - a_1 c_2 = 0, there would only be one solution. But since the full solution in the pdf is so complex, I do not see which constraints would lead to cancellation there.

\---

And that is not the full problem I was trying to solve. In the full problem there are constraints on the a, b, c, d. There is a given graph, and depending which nodes are connected in the graph, the constants are the same. Like if node 3 and node 7 are connected, then b_3 = c_7 und c_7 = b_3. (even more complex though). And then the question is, do these constants cancel in the solution of those equations? And the final problem we want to solve: which graphs lead to exactly one solution, and which graphs lead to no solution of the equations?

</comment><comment><USER21> >"the faculty will not accept asymptotics"

the hell does that mean?

<comment><USER22> (Math professor here).

Ambiguous and poorly explained. (Note the question immediately afterwards asking for clarification.) But probably something along the general lines of "My advisor said that, if my main theorem is an asymptotic estimate instead of an exact formula, then this would not be judged to be novel/strong enough to earn a Ph.D."

<comment><USER23> If you don't mind, could you explain the practical difference or the reasoning behind such a requirement? Are there situations where boundaries appear to be asymptotic but the exact solution shows this not to be the case?

<comment><USER24> I re-implemented a quasi-polynomial algorithm. Experimentally, it shows exponential behaviour. Back-of-the-envelope calculation shows this behaviour can continue until the input size is >>10^21 before the asymptotic bound asserts itself. (For comparison, input size 30 is unfeasible)

<comment><USER25> Which algorithm?

<comment><USER24> Parys' quasi-polynomial algorithm for solving parity games, [https://arxiv.org/pdf/1904.12446.pdf](https://arxiv.org/pdf/1904.12446.pdf)

Note, another implementation doesn't have this behaviour for the family of inputs I use. It's an implementation detail that has no effect on correctness. Thus for the other implementation another family should exist.

</comment></comment></comment></comment></comment></comment><comment><USER26> I'm totally sympathetic with feeling the clock ticking for a PhD thesis submission (been there), however:

I knew I could take this route but never did it. This is a bit of a mockery of the whole purpose of a PhD thesis (it has to be _your_ work primarily).

This is just an advanced version of posting homework questions on the internet.

</comment><comment><USER27> This seems like a deeply flawed qualification, that smart people, noticing interesting properties of deep problems, are forced to panic in such ways.

<comment><USER28> On the surface, I agree: there's an interesting problem that's worth solving, and a purely artificial limit is forcing people to do a bang-up job at solving it.

But if you dig a bit deeper, I can see two counter-arguments:

1\. The _real_ risk -- by which I mean "the risk I have most often observed in the wild" \-- is that a Ph.D expands to fill the time it's given, without ever wrapping up and producing a publishable result. This happens so often that it's practically expected in some places.

2\. Having a deadline, oddly enough, also serves as a catalyst for birthing an idea... for "pinching it off" as the expression goes. At some point you have to stop planning and start executing. You can see the deadline as a forcing function.

Ph.Ds are needlessly traumatic and procedural in many ways, but I'm no longer sure that hard deadlines are a net negative.

</comment></comment><comment><USER29> This kind of "social media" gives me faith in the ability of humanity to survive and thrive in the future.

</comment><comment><USER30> You don't often see mathematics emergencies.

</comment><comment><USER31> Low quality comment, but this once again confirms what I already knew: I suck at math.

</comment><comment><USER32> Wisdom of the crowd in action.

I feel like this wisdom isn't tapped into enough. We're often burdened with individual tasks and challenges while utilizing crowd knowledge is looked down upon or seen as an inferior solution finding mechanism. e.g. Imagine if companies worked together to figure out self-driving cars rather than compete?

<comment><USER33> There's the Autonomous Vehicle Computing Consortium (AVCC): [https://www.avcconsortium.org/aboutus](https://www.avcconsortium.org/aboutus)</comment></comment>


Intrinsic - <AUTHOR> https://intrinsic.com/solutions/engineers <comment><USER2> so pledge but for node only?</comment>


Portland Seed Fund seeks inspiration from Y Combinator grads - <AUTHOR> http://www.oregonlive.com/business/index.ssf/2011/04/portland_seed_fund_looks_to_ca.html <comment><USER2> Feels like most of the people in Portland need to figure out what they want first.

At their software industry summit, after a long series of surveys, the takeaway was that people in Portland value quality of life over making more money. That's great, but that's not what's going to drive serious entrepreneurs to Portland. So I'm not sure why this would lead the idea that we need more funding here for startups. And to top that, the Portland Seed Fund along with most of the other funding networks in Oregon are pay to apply.

At a the recent UpdatePDX event[1] one of the comments was "Several people commented on how lovely Portland was – even in the rain. But damn, they wish they could hire the types of people they needed here."[2]

The conclusion that I keep coming back to seems to be "There aren't enough people here ready to dive into a startup, yet everyone thinks we need more startups and likes that idea, but we value our quality of life more anyway." I'm afraid that this is just a huge setup for more pay to apply and pay to mentor programs designed to profit off this notion that we need to have more startups in Portland. Call me skeptical, but I just don't see all the movements in Portland leading anywhere significant.

[1]<http://www.meetup.com/updatepdx/events/16416694/> [2][http://www.chesnok.com/daily/2011/04/05/updatepdx-nosql- oper...](http://www.chesnok.com/daily/2011/04/05/updatepdx-nosql-operational- complexity-and-hiring/)

P.S. And I'm saying this as someone who just moved his services business into Portland.

<comment><USER3> One thing Portland really doesn't have compared to the other West Coast cities is a good university. (Sorry Portland State, it's true). I don't see that being fixed anytime soon, so that's always going to cause a problem for recruiting new grads.

<comment><USER4> I have to disagree here both Oregon and Oregon State are underrated universities. I'm a bit biased towards Oregon State as I graduated from there but their Engineering and Science colleges do a fantastic job.

<comment><USER3> Neither is actually in (or especially close to) Portland, though, right?

</comment></comment></comment></comment><comment><USER5> What should the role be of (local) public money in private investments?

<comment><USER4> Good question, does anyone know if they're using public funds as a loan instrument or are they taking equity in these companies?</comment></comment>


College: The biggest scam we'll ever buy - <AUTHOR> http://marcanthonyrosa.com/college-the-biggest-scam-well-ever-buy

<comment><USER2> Education is what you make it.

If the grading structure is so rigid and foolish, then it ought to be trivial to game it, leaving almost all your time free to get laid/start a business/contemplate the human condition to your heart's content.

If you choose to spend your time trying to eke out as many marks as possible from each minute spent cramming, then I'd wager you probably aren't imaginative enough to be ultra-successful anyway. Aim to leave university having done something so cool that your eventual grade is rendered irrelevant, (ideally so irrelevant that you can drop out.)

 _"But these benefits cannot completely justify a system where creativity and genuine learning isn't properly rewarded."_

If you're in your 20s and you still need to be "rewarded" by a teacher giving you a shiny gold star then again, something is wrong.

EDIT: upon consideration, I am putting across a somewhat elitist view here. Not everyone can be expected to "do something so cool that your eventual grade is rendered irrelevant," to transcend their peers in order to gain value from their degree; that's a contradiction. There are indeed many flaws in the system and it is unreasonable to say "just hack your way around them for your own benefit!" when we could just fix the system so one can take the normal, average route though it and still get value from one's money/time.

In lieu of that though, I still think what I said stands, although I didn't have to pay american tuition fees.

<comment><USER3> >Not everyone can be expected to "do something so cool that your eventual grade is rendered irrelevant," to transcend their peers in order to gain value from their degree; that's a contradiction.

Not everyone, but those who plan to be mentioned along with "Steve Jobs, Alexander Flemming, and Adam Smith" certainly can.

<comment><USER2> You can't design an education system just around those people though.

<comment><USER3> Right, but the original article was saying the education system is bad for those people, and my point is your original comment wasn't elitist, it was a valid response to the complaint in the original article.

<comment><USER2> Also, I don't think the christ-figure of apple corp is in the same bracket as the discoverer of penicillin and the author of wealth of nations, but I don't imagine arguing about that is going to get us anywhere. Just wanted to register my dissent.

</comment></comment></comment></comment></comment><comment><USER4> I'd argue that college is the _perfect_ medium for learning about creativity: creative opportunities don't fall into your lap. Your first novel, album, or photography exhibit won't materialize from air--you have to _work_ towards them. (That explains why I haven't made music yet!)

Students can be creative in writing or painting classes, robotics lab, go-kart engineering shops, or even on their political science papers or statistics projects. None of those are required (maybe the papers and projects), just like writing a novel isn't a pre-requisite for _life_ , but students have the option to participate.

Again, to beat a dead horse a little further: college is _what you make of it._ If you memorize bold words, you're ready to file TPS reports; if you take that pottery class or join the robotics competition, you're ready to enjoy all of life's dimensions.

(Also, I flagged this because (a) it's another college-bashing piece and (b) it has possibly the worst argument against college I've seen so far.)

</comment><comment><USER5> _Maybe, just maybe, the college system isn't as perfect as we'd like to believe. Maybe, just maybe, we've been learning the entirely wrong lessons._

Maybe, just maybe, this theme is a little tired. I keep hearing this, and I keep believing it. Cramming for tests does not a creative person make. But neither does sitting around talking about your creativity. Ultimately creativity comes from what we do and make, and college is nowhere near perfect for that, but then again college can't optimize for _anything_ , because there are far too many things it might prepare a student for, however well.

Incidentally, I don't believe college should be placed on the pedestal it often is, to the point that wondering if it's "as perfect as we'd like to believe" is the wrong question entirely. e.g. <http://www.paulgraham.com/credentials.html>

</comment><comment><USER6> I never crammed for a test. Aside from courses that I liked (like History and English) I never took anything outside of CS. I dropped out after ~ 3 years to write software for a living.

This worked okay in 1982. I don't know if it would work now. I /do/ know that when I interview someone I never really look at their degree or coursework except as a starting point to figure out if they're a good hire.

There are two other people within fifty feet of me who have a similar educational story. We work at a very large company and you've probably used our products.

As far as I'm concerned, college is what you make of it. If you're going there purely for a degree and you don't learn anything useful, that's going to be a problem. If you go and learn something and can demonstrate that, you're good. I don't care if you went to Podunk or MIT, I don't care if you have the piece of paper or not; if you have the chops, you've won.

</comment><comment><USER7> The first two sentences of his last paragraph:

"Is college really a scam? Most likely, no."

Thanks for admitting your title was linkbait?

Also, it's fine if you're going to complain about the college experience, but please offer alternatives. It's much easier to bitch than to come up with solutions.

</comment><comment><USER8> I am pretty much as anti-college as it gets, but this piece really doesn't lay out the best arguments for why our higher education system is failing us.

This doesn't sound like an argument against college in general, it sounds like an argument against really bad colleges.

The problem I have with college is that it tries to do two very different things: 1) Prepare students for participating in the market economy 2) Provide learning for the sake of learning

It's best to separate these two things. First of all, doing (1) shouldn't take 4 years for most people. And it definitely shouldn't be four years of classroom learning interspersed with summer's of "real work."

And doing (2) is something that shouldn't be tied to how we sustain ourselves economically (i.e. getting jobs). Learning for the sake of learning really needs to be limited to those who: (a) have an aptitude for it (b) have the passion for it Otherwise, you're pretty much wasting everyone's time.

How would this look in practice? I don't know, but I bet will start seeing this pattern emerge.

The demand probably won't come from students. It will come from cashed up employers who desperately want to hire, but see long lines of unemployed grads who have no clue how to make themselves useful.

</comment><comment><USER9> God, college was fantastic! Talk about the greatest 4.5 years of my life. Here's why:

I was in Engineering, where they drill math into your heads for the first 2 years, and you don't see a lick of a practical application for it, but looking back, that was incredibly useful.

I found more creative outlets then I could possibly imagine. I had friends in the fine arts who could teach me how to paint, and let me play around in the photography darkroom. I dabbled in getting a minor in philosophy (but found the meaning to life, and decided I didn't really need to go any further in it..) I planned practical jokes and embarked on poorly thought epic adventures with roommates. I wrote in my spare time (inspired to write out thoughts by my philosophy teacher) I met friends who played guitar as well, and we made wrote goofy songs that annoyed the neighbors, to blow of steam.

The social aspect was AMAZING. I participated on two club sports teams, joined philanthropic causes and met some of the most inspiring people from all walks of life, I threw the greatest parties and after-parties in the history of life, (I was somewhat shy in high school though, THAT changed) I now have more friends than I know what to do with, and an available couch to crash on in every major city in the Northeast (and several in the Midwest and CA)

I was free. It's not like most of real life, with serious financial responsibilities. No day was the same. If life sucked, in four months a new semester would be here, and it would be different.

Lastly, it opened doors. I have a career that pays well (thanks, valuable engineering degree) I have connections (be it social or business), and it was so damn tough (at least at times) it gave me the confidence that if I put enough effort into something, I can build it, and succeed. _Priceless_

edit: I didn't build anything awesome in college, or get a startup going, or discover the cure for cancer, but it gave me tools to do so, the rest is up to me.

edit #2: I spent a semester in Florence, Italy. I sat in museums and sketched, I took a history and culture of food class, I was exposed to so much diversity in thought/way of life/culture. I became exceedingly good at picking up non- verbal communication, which is VERY useful in real life (Took my first Italian class while there...). It was my first time living in a city, now I travel frequently, and move with comfort in a city. Sans travel expenses, it wasn't any more expensive than my public school tuition and room and board.

</comment><comment><USER10> I'm not sure I get what this guy is getting at. I've been through 2 colleges in 2 different countries (BA and MS) and am on my second job right now right after my MS. Not to list my credentials or anything, but in general no matter where I go, it's always a systematic thing that we as humans created and we have to tackle. The biggest challenge in a job is not the job but the organization.

Organizations aside, even in startup land or various just small companies as you know it, there are restrictions, in different forms. Customer satisfaction, for one. Investor pressure, as another, and they can be restrictions, or challenges depending on how you see it.

My problem with college is that for most of the folks, when they get into college, they don't really know what they want, with the new found freedom and gets distracted by the various frat like bonding activities that goes on in the campus.

///

I don't think creativity exists in some sort of pure unadulterated sort of vacuum where an individual is "free". Philosophically speaking, no one is ever "free". No one wants to be either.

Truly successful people are successful despite of the system. They are successful because they know how to break out of the system. They understand (metaphorically speaking) the system and how to cross the line so that the create something new. That, is creativity.

Unfortunately, my opinion is that most people try the best to construct some sort of structure to "teach the young", so to speak; I don't think there's any malice in there. The truth is, you can't teach people to be creative. You can teach people to be different, but if different becomes the norm, then different is no longer different. To be truly creative, one needs to have a good combination of observation, introspection, good working ethics (i.e. slog through the details) and willpower.

</comment><comment><USER11> I think I might have some perspective to comment on education. I dropped out of a large public institution in a technical program to work in industry for a while. Many of my motivations were similar to the authors complaints.

Is education a scam? I think it is what you make it out to be. If you major in Communications and spend all night fratting it up, then yes you could have a case that education was not useful to you. Even then you are deriving utility because you are practicing your people skills and creating a network useful in your future career.

I don't find his complaints about scut work particularly compelling. It happens in industry. Get used to it and stop whining.

I think that the biggest problem nowadays is that we immediately push students to college right after high school. For a subset of highly motivated students, this is the right move and they often thrive in college. I do think the majority could benefit from a year or two to find themselves. A semi-mandatory national service program might be a great idea since it would carve out a time for this express purpose. Students would no longer feel they were behind if they did not immediately enter college. The time spent in college would also be spent more productively.

Ultimately I plan on going back to school. I think there are something like six genealogical hops between Thomas Hobbes, Adam Smith, and John Stuart Mills. For better or worse, the most brillant minds who produce the ideas which civilization are based around or usually found in universities. One simply cannot get that kind of personal mental exposure to them in industry.

</comment><comment><USER12> You didn't explicitly go over how creativity is stunted other than saying it isn't rewarded. College teaches you new facts, it is extremely objective in it's teachings so that later on you can expand your ideas and creativity upon what you learned subjectively. It s a great place to expand upon things that have already been discovered in a structured manner allowing you to specialize in a timely manner (as compared to learning on your own).

Maybe I'm just biased, but if you find my ideas odd please inform me of why you believe so as I'd love to hear!

</comment><comment><USER13> To add to the chorus: college is what you make it. I haven't finished my degree, financial reasons caused me to pause (27 now, going back will be weird). But I'll be back. Honestly, even when I graduate I'll probably still pop in for the occasional literature course or odd class I hear of that's interesting. College is a great place for discussion, flexing new ideas, and just general growth as a person. But, it's not for everyone.

I've seen a few articles like this pop up on HN and it always reminds me of this article I read a few years ago:

[http://www.theatlantic.com/magazine/archive/2008/06/in- the-b...](http://www.theatlantic.com/magazine/archive/2008/06/in-the-basement- of-the-ivory-tower/6810/)

I think it's worth mentioning that many of the reasons I enjoy college, and college classes, are the same reasons I love coming to HN. I am not a programmer, I do not work for a startup, I'm actually a literature student working in a support role that has little to do with technical skill. I come to HN because I enjoy a forum filled with intelligent discourse, where most visitors understand that intelligent people can disagree.

edit: I should also add to that list of reasons I like to keep up with computer and technical news, too :)

</comment><comment><USER14> College, and school in general, is a strange game indeed. Probably the only way to get through it unscathed (or with minor scars) is with an intense amount of perspective, that is, not taking it too seriously. If you mold your very being around "winning" at school, you are probably hurting your ability to win at life -- to be successful or even fulfilled.

I wish I knew then what I know now, but I hope to teach my kids healthy priorities and time management skills.

</comment><comment><USER15> > Is college really a scam? Most likely, no.

Might want to re-title your article then.

</comment><comment><USER16> Maybe you should consider transferring then? College is there to increase your breadth of knowledge. Ask yourself how many of your friends who never went to college critically analyze the world around them or have well thought out discussions about things bigger than themselves (cosmos, patterns in the world, science, etc). Remember, SA is the exception!

Creativity comes from limits (and knowledge). In art schools, students are told to only use certain materials for a reason. Why do you think we have coding competitions where the winner has the fewest lines of code or can do the most in 48 hours?

While I can understand your viewpoint, it just sounds like you need to either change your major or school or both. I went to a university where we had to co-op (read lots of internships that didn't involve getting coffee) and my core classes depended on mostly group projects solving problems. It is precisely because of this education and my breadth of knowledge that I have ideas connecting completely unrelated ideas.

</comment><comment><USER17> This is such a shallow mush of generalities, that it's pretty much worthless as a critique of higher education.

"these benefits cannot completely justify a system where creativity and genuine learning isn't properly rewarded."

Anyone who has ever taught at the college level will quickly realize how wrong that sentence is. Any undergraduate who shows the _slightest_ amount of spark, imagination, initiative, and hard work gets rewarded (as they should) with good grades. The ones who get punished are those who game the system by trying to get the highest mark for the least amount of work. These latter are usually the ones who complain that creativity (i.e., their own rank laziness) is not being "rewarded properly" (because, ummmm..., the school isn't making the next Steve Jobs... or DaVinci, or someone like that...).

You want your creativity crushed and your initiative smothered? Try _working in a job_. School is an absolute blast compared with what the rest of your life will feel like.

</comment><comment><USER18> I actually don't agree with this at all. Everyone loves to hate on college, but personally and professionally on average there is a world of difference between people that come from a good school and a bad school.

We are all lazy, I would rather have fun and party; that's a no brainer. However, rigor and competition and some metric(grades) to compare students is what pushes and motivates them to succeed. Creativity is possible in creative subjects, if you take drama, music, or art grading is going to be very different than in chemistry or physics. This has nothing to do with the system, and more to do with subjects.

Not everyone thrives in the system, but not everyone gets joy out of learning either. Problem is that there are a few good schools and a lot of bad schools, so on average you'll hear poor experiences, but this is suffering from the silent evidence effect.

</comment><comment><USER19> > We can learn all we want, but GPA is the end-all on how well we understand > material and, subsequently, prepare around it.

Interestingly enough, in the ten years and probably fifty job interviews I've had since I graduated from college, not once was I ever asked for my GPA. (The only time in my life was once for a summer internship, _during_ college.)

In college, I wasn't sure if my strategy of trying to genuinely learn, and not cram for tests or cater to teachers' whims, would serve me or burn me. Turned out it was very smart.

But that may only be because I went into software later on, where employers care mostly about the skills you demonstrate in interviews. Whereas for people in law and medicine, it appears your GPA matters a great deal.

<comment><USER4> I've been asked once. The person had just asked me how many ping-pong balls fit into the room we were sitting in, so that should tell you something about their interviewing abilities.

<comment><USER20> It is actually one of those famous interview questions. Kinda like the Microsoft one where they asked you why are manhole covers round. Totally useless, since performance in an interview is not indicative on whether an employee is a good fit or not.

<comment><USER4> I know! It's always defended as a way to "see how the candidate thinks," but that only invites pop psychology assessments. Whatever, the person was a jerk regardless.

</comment></comment></comment></comment><comment><USER21> Private collage + faculty dependent tuition concession, jerks. :) Nice education, no debt. But we can't all be faculty dependents.

The computer-science parts were helpful but not super-helpful; Real Experience was more helpful. The art minor was fun. I learned to appreciate some other things like the mandatory English courses a while after I stopped taking them. I don't know how to make students like my past self better appreciate those things in advance so as to take advantage of them. I think it's a bit of a problem for most students.

</comment><comment><USER22> It's only a scam if you pay too much for it.

At $2200 a semester (before scholarship), I'm paying roughly $100 a week to use campus facilities and have access to my professors time. Considering I spend 10 hours in class and my professors all have 5 or so office hours each week, I think I'm getting a pretty good bargain.

Although, BYU is an exception. Most other schools aren't really the same bang for your buck.

</comment><comment><USER23> This is clearly link bait.

Title: "College: The Biggest Scam We'll Ever Buy"

Conclusion thought: "Is college really a scam? Most likely, no."

</comment><comment><USER24> The purpose of school and college isn't training. It's education. People that confuse the two will be very disappointed with the results.

</comment><comment><USER25> This guy should have gone to Evergreen

<http://www.evergreen.edu></comment>


Show HN: Page-info – Determine the attributes of any region of memory - <AUTHOR> https://github.com/travisdowns/page-info <comment><AUTHOR> Sometimes you just want to know exactly what type of page is backing your memory region - because the behavior of 2MB huge pages can be very different than normal 4KB pages - and when using transparent hugepages there is no guaranteed on what type you will get (and you might get a mix)!

This mostly trivial utility lets you query the page type at runtime - <USER2> you to answer the above question exactly, as well as others like "has this page been committed yet?" or "has this page been swapped out?".

Feedback welcome.</comment>


Adobe Flash/Flex. Plague of the Web. - <AUTHOR> http://kontsevoy.blogspot.com/2007/11/on-flash-and-new-technologies.html <comment><USER2> Some of the things you said I could not agree more with. After the countless time spend trolling around YC, Slashdot, Engaget, Gizmodo, Techcrunch, programming, all that jazz...the knowledge that gets picked up becomes obsolete in a small amount of time and well, staying entirely on top of things all the time can really be more trouble than its worth, especially if you're a student who needs sleep, or if you don't stay on top of classes and work.

</comment><comment><USER3> It's either Flash or hacked together Ajax.

Or Microsoft is perfectly happy to sell you on Silverlight.</comment>