Math professor forced to use $180 textbook written by his boss - <AUTHOR> http://www.ocregister.com/articles/bourget-688288-math-book.html <comment><USER2> I'm actually surprised that there's no policy on conflict of interest for these universities. It's one thing to be charging through the nose tuition, that's just further exacerbated by these professors that wring students for personal gain.

Writing your own book is fine, but manipulating these books EA style (where you buy a game that comes with a one time use multiplayer key, neutering your ability to sell it afterwards) on the thinly veiled "improvements" is just downright shady. I commented about this on the other math book to pdf submission, but I had a professor did just this. He basically shuffled chapters around and renumbered problems, making the previous year's book worthless because the problems he assigned are numbered out of the new book, and he refused to provide any mapping of new problem sets to old problem sets. I had mentioned this to the department heads and none of them really cared at all about this practice.

<comment><USER3> You are surprised? Have you been to an American University? It would be far more plausible if you had said "that's exactly what I would have expected"

<comment><USER4> I graduated four years ago, and am currently in grad school.

As an undergraduate at a small private college, I can only recall two professors who required their own books. One was a paperback physics reader for a very large class, available from the department for $20 (or from upperclassmen for less). The other was for a small math class, was not unreasonably expensive, but also was not very good, but when the professor left halfway through the semester with health problems, the department bought us all copies of the new book. My professors were always accommodating to anyone who wanted to buy an older edition, and in one case explicitly told us not to buy the expensive new edition.

In my current department at a large public university, I know of only one professor who requires his own book. It's about $40 and has only had one edition since it was published 15 years ago. In most lower division classes we use an in-house online homework system, although we don't have a good database of problems for differential equations, so we've typically required the latest edition of Boyce and DiPrima so students can use the publisher's homework system. But we've started work on our own problem sets, and we are at the point where we can use our own in-house homework system for it, if the professor is willing to put in a bit more effort organizing and debugging homework.

Anyway, this sort of exploitation is not typical in my experience.

</comment></comment></comment><comment><USER5> As a student right now I staunchly refuse to ever pay full price from a textbook, and if possible to not pay for one at all. The prices we're charged are ridiculous, and the way professors profit even more so.

The worst example of this is, and I have no qualms about publicly calling out this professor, is Dr. Alan DeSantis at the University of Kentucky. DeSantis is rather prolific, he gets a lot of press for the university, and I'm pretty sure he's our highest rated prof on RateMyProfessor, so I'm sure he knows he can basically just do whatever he wants.

But for his freshman COM101 class, a class where you can basically get all the content out of by just reading the Wikipedia entry on a handful of pop psychology phenomenons, he required us to purchase a $40 "workbook" for taking notes in. But this "workbook" was, quite literally, just his lecture powerpoints with random gaps in sentences.

During lectures we had to fill in the blanks as the slides came up, or else we'd have no idea what was going on because he used his own terms and names for pretty much everything he was talking about.

<comment><USER6> Wow that sounds like an insulting educational experience.

As if the teacher was really teaching "How To Be A Jerk." or "How to Copy And Paste."

</comment></comment><comment><USER7> I had a math prof in college who would create a custom textbook for each class week by week in latex... it was amazing.

<comment><USER8> I had a couple professors in college that created their own textbooks for teaching and didn't charge students for them.

Some of them were good, but some were obviously poorly edited and explanations were identical to lectures.

</comment></comment><comment><USER9> Last I heard you couldn't "force" a tenured professor to do anything. Dismiss over a text book? laughable

<comment><USER10> 51% of Cal State Fullerton profs are adjuncts [1], so I'd assume this professor can be fired fairly easily.

[1] [http://www.collegefactual.com/colleges/california-state- univ...](http://www.collegefactual.com/colleges/california-state-university- fullerton/academic-life/faculty-composition/)

<comment><USER11> I had the same thought, but he appears to be tenured (has taught there 9 years, and is an associate, rather than assistant, professor): [http://math.fullerton.edu/people/full-time- faculty/item/bour...](http://math.fullerton.edu/people/full-time- faculty/item/bourget-alain)

<comment><USER10> Thanks for digging, I was surprised his employment type wasn't mentioned in the article, since it seems like it would play such a huge role in this.

</comment></comment></comment></comment><comment><USER12> For anyone wondering since I didn't see it in the article, it seems like the $76 book is "Introduction to Linear Algebra" by Gilbert Strang. Not sure about the free book though.

</comment><comment><USER13> I'm currently teaching out of Stewart because that's what the general curriculum for our department is. Stewart died an insanely rich man, and I'm sure will keep making slight modification of his calculus textbook from the grave.

However, I tell my students in the syllabus, which I post online well before the class starts, that calculus is centuries old and that they are not required to pay through the nose for this textbook. I regularly go out of my way to facilitate using older textbooks.

</comment><comment><USER14> Hmm:

>"You acted contrary to department policy when you did not use the single assigned textbook for MATH 250B sections," the school reprimand states.

Universities may be large institutions that require many decisions to be put on autopilot with official policies, but this issue seems like a clear example of something that is not unimportant enough to be handled with use of "policy" as a magic word. As colleagues that hopefully possess some intellectual sophistication, they should at a minimum explain their interpretation of the relevant policies and why their impact is positive, or alternately explain why the policy is worth preserving in the face of producing a worse outcome in this specific instance.

Considering that according to the article, the past two governors of the state for the entire university system have pushed toward a greater attention to textbook prices, it seems even less likely that a department can get away with undermining the ethical standards of the American Association of University Professors by using the word "policy" like some talisman.

</comment><comment><USER15> This is normal at my school as well.. Typically if I bought everything on the syllabi of the courses I'm taking, my bill would easily be greater than $300. Probably even closer to $500. Pretty much books that cost anywhere from $150-250 or so each, with even used copies at least half if not more of the price for a new copy.

</comment><comment><USER16> >However, with a multi-section course, which is the case in Bourget's situation, "the individual (faculty member) would have to work with the other people ... to make the best decision together on what those materials would be,"

What exactly do they mean by multi-section?

In college I had a very large, expensive calculus book that covered 3 semesters of calc classes. In that case I appreciated the uniformity of using one mandated textbook.

But if that is not what they meant by "mulit-section" then I question why such strict enforcement.

By and large most college textbook requirements do feel like a scam, and it only seems to be getting worse over the years.

<comment><USER17> Multi-section most likely means that there are several different sections of the same course running simultaneously. In addition, there are probably different professors teaching these sections.

I can understand part of the argument here - it would be important to maintain consistency among the different sections, so that students who take the class from Professor A learn basically the same material as students who take Professor B. That being said, the material presented in a low-level class like this hasn't changed in a long time, so any book should suffice.

</comment></comment><comment><USER18> I did have a professor that taught the class with the textbook he wrote. To prove that he believed in the book and not the revenue, he donated the royalties from our class from the book into the student fund.

<comment><USER13> Any professor who understands the first thing about marketing and adoption should do this. Jack Lee taught me smooth manifolds out of his own book that he gave to us for free. 10 years later, I'm teaching out of that book, so my students are paying for it.

</comment></comment><comment><USER19> > soaring textbook prices

Yeah textbook prices are really out of order --- the calculus text at my university is $130+, which is just insane.

<selfplug>Anyone interested in a cheaper option for mechanics + calculus should check out my text: [http://noBSgui.de/to/MATHandPHYSICS/](http://noBSgui.de/to/MATHandPHYSICS/) </selfplug>

</comment><comment><USER20> Students should pitch in for one copy, scan it, make a PDF.

And then just to be a dick, post it online on some Chinese/Russian server and email the link to the professor anonymously.

</comment><comment><USER20> I wonder what stops a professor of a required class to charge $1,800 per book. Or $18,000.

</comment><comment><USER21> It's probably past time to be recording all audio and as much video as possible when you are not in your home.</comment>


Starbucks serving wine is a good idea - <AUTHOR> http://internationalbs.wordpress.com/2010/10/27/starbucks-could-be-onto-a-corker-of-an-idea/

<comment><USER2> It may be a good idea, but it is going to be very difficult to implement across the United States. Licensing for serving alcohol is extremely complex, licenses are scarce in many states, and liability issues are huge.

I'd be shocked if this ever rolled out to more than a few stores.</comment>


Will Microsoft Break the Internet? - <AUTHOR> https://www.inc.com/geoffrey-james/will-microsoft-break-internet.html <comment><USER2> _if a single company is destined to dominate the future of the Web, I 'd damn sight rather it be Microsoft than Facebook_

In an earlier era, it would have been better for it to be anyone _but_ Microsoft. So it doesn't matter who, just as it isn't whoever is the biggest at the time, just to become the same. So no, the only answer is for no one party to dominate.

<comment><USER3> i think the user should dominate the internet. just like prebrowser era. so many people have been trained to think the browser is the internet, and the real internet is somehow a deep,dark net that should be feared.

</comment></comment><comment><USER4> The title of this piece is bonkers. There's nothing about breaking anything. Also two pretty glaring spelling errors, screaming no body took two seconds to proofread this before shoving it out the door.

</comment><comment><USER5> Someone had to do this. Microsoft hasn't done anything innovative for years, so if they can pull it off, kudos!</comment>


Toxic Coworkers Are More Expensive than Superstar Hires - <AUTHOR> http://qz.com/563683/turns-out-toxic-coworkers-are-more-expensive-than-superstar-hires/ <comment><USER2> I worked in a toxic environment, developed a mental illness from the stress and it ruined my career.

I was looking for another job to escape the toxic environment but I could not quit because my family needed house payments. So I ended up on disability as a result.</comment>


Express NPM module has 292 dependencies - <AUTHOR> https://medium.com/friendship-dot-js/i-peeked-into-my-node-modules-directory-and-you-wont-believe-what-happened-next-b89f63d21558#.qebco48rc <comment><USER2> Comments moved to [https://news.ycombinator.com/item?id=12235789](https://news.ycombinator.com/item?id=12235789), which was posted earlier. We'll leave the original title on that one since it's satire.</comment>


Google Flips Switch on Real Time Analytics - <AUTHOR> http://campeaux.com/2011/03/google-analytics-real-time/

<comment><USER2> Of course your analytics figures will keep going up. They were never frozen, you could always see "The very latest data that Google has processed".

The key word here is "processed".

Depending on your site, and GA, there will always be some delay. i.e. if I visit your site now, My visit gets recorded with GA. GA processes this as quick as it can. Once it has processed it, (And then updated all its corresponding data sets, everything from browsers, to goal completions etc), then you'll see it.

The thing with "Real Time" is that whilst every analytics app out there claims to have it, the ones most likely to have it are the ones with least customers. There is some delay inherent in an analytics tool that processes data. Otherwise it's just a tail of your server log.

If you want to play and measure how real time things are, set up a Profile for your site that includes only visits from your IP. Or set up a new page on your site with a URL only you know about. That'll let you see how quick it is. (Hint: It's pretty fast when you take into account the scale of the challenge)

I wrote this run through of analytics tools, which you may have seen [http://www.contrast.ie/blog/the-future-of-analytics- products...](http://www.contrast.ie/blog/the-future-of-analytics-products/)

Hope that helps.

Des

<comment><USER3> If there's a huge amount of pageviews, the delay is even longer than 24 hours in GA. For one of my sites, the numbers keep going up until more than 24 hours after that day ended. This is annoying because the interface does show the day as being completely processed (i.e. it includes the day by default when you open up the reports).

</comment></comment><comment><USER4> Current day's data has been available for me across 5 different user accounts and dozens of clients for at least a year. You just have to select today to see it.

It sometimes lags by about an hour.

<comment><AUTHOR> In the past I have been able to select the current day... but the reporting for the day always remained at zero. Only until the following day were stats from the previous day available.

</comment></comment><comment><AUTHOR> Can anyone else confirm this? I'm monitoring my Analytics account right now and I keep seeing the figures for today's visitors go up (with page refresh).</comment>


Firebase Leaves Beta Today - <AUTHOR> https://www.firebase.com/blog/2013-08-15-firebase-leaves-beta-today.html

<comment><USER2> Before I worked for ReadyForZero and before I started Light Table, I built a whole bunch of "real-time" infrastructure for a little live-blogging as a service company I started called TypeWire. It was miserable, difficult, full of quirks, had very unusual scaling characteristics and just a huge mess. I sincerely wish something like Firebase had existed back then, because it would've completely trivialized what I was trying to do. And that's the way things should be. We shouldn't be constantly rebuilding infrastructure, we should be solving problems - and Firebase is a wonderful way to get you back to solving problems.

I've been good friends with these guys for a while, and I'm impressed with how well they've done, how much people seem to love the service, and just the general quality they instill in what they do. Congratulations guys, it's been awesome watching you get to here.

<comment><USER3> This is one of the reasons I'm absolutely itching for the Light Table plugin system -- it'd be awesome to collaboratively edit (and maybe evaluate!) code using Firebase.

Can't wait!

</comment></comment><comment><USER4> Congratulations! Firebase is very compelling.

Personally, I have been trying to determine if I should buy or build a new mobile game backend that has an average of 50-250K iPhone app downloads/month. I'm adding online multiplayer to an otherwise single-player game.

I've looked at Firebase and a number of other offerings include Exit Games' Photon Cloud. Firebase had seemed to be expensive for my use case of ~ 400K MAU. However, Firebase's experience of 1 CCU = ~ 1400 MAU [1] would be easily supported under the "Candle" or "Bonfire" tiers which are not expensive.

Exit Games' has a different experience [2] but I'm probably comparing apples to oranges a bit. Games vs Big Brother. Well, there is Roll20 so maybe it's at least comparable experiences.

1 CCU = 1400 MAU vs 1 CCU = 20 MAU

That's a big difference. Am I thinking about this strangely?

[1] "In our experience, 1 concurrent corresponds to roughly 1,400 monthly visits." [https://www.firebase.com/pricing.html#pricing- faq](https://www.firebase.com/pricing.html#pricing-faq)

[2] "To calculate monthly active users (MAU) we assume a CCU to translate into 10 daily active users (DAU) and each of these into 20 MAU" [https://cloud.exitgames.com/Pricing](https://cloud.exitgames.com/Pricing)

<comment><USER5> The stat listed on our site is for a typical website. If you have a mobile app, or an atypical website, your mileage may vary. Even for highly engaging, paid apps I suspect you'll find it's in the 100 to 1 range (or more). 1 CCU = 20 MAU is very high.

For example, World of warcraft peaked at ~10% of their users online at any one point recently: [http://venturebeat.com/2012/11/07/wow-pandaria-1-million- con...](http://venturebeat.com/2012/11/07/wow-pandaria-1-million-concurrent- players-in-china/)

Also note that we bill at the 95th percentile, not peak usage, so you can spike well above those numbers without consequence.

If you want to know how many concurrent users you'll need, sign up, drop in our script, and have your clients connect to Firebase (but do nothing). You'll be able to see concurrent user counts under Analytics in Forge.

<comment><USER4> That's a valuable data point about WoW; thanks!

I like your idea of just adding Firebase and testing the waters. Alas, the next version of my app is a rewrite to Unity3D and there is no Firebase client for Unity3D (yet?) so this amounts to just feeling things out.

</comment></comment></comment><comment><USER6> I love Firebase and was planning on using it as a back-end for a JavaScript game I'm making. However, since there doesn't seem to be a way to prevent cheating without adding an extra server layer I had to drop the idea.

Something as simple as preventing people from just manually setting their own score on a leaderboard seems to be impossible. I would be very happy to be proven wrong though.

<comment><USER5> I'm guessing you were using Firebase before our security and validation rules were released. We now have a very powerful method for controlling data access and validation that can secure your data.

There's a screencast on our website that explains how this works here: [https://www.firebase.com/docs/security- quickstart.html](https://www.firebase.com/docs/security-quickstart.html)

<comment><USER6> Thanks but I don't see how security rules will prevent someone from manually setting their own score. Take your 404 Astroids game as an example. Right now anyone can set their own score as they wish. Is there a way to prevent that using security rules?

<comment><USER5> You can enforce this as well as any other backend can. Games are a bit of a special case because you not only want to enforce access controls and a particular data model, you also want to make sure the client didn't "cheat".

It turns out this is an issue with any game that runs on the client though -- regardless of if you're using Firebase or not. Preventing cheating is tough because at some step in the process here you're relying on the client to tell the server the truth. Since the game runs on the client, you can't ensure that the code hasn't been tampered with, or that an AI isn't playing the game, or that the user hasn't cheated is some other way.

With Firebase security rules, you can enforce that only that user can set the score, and you can enforce that the score is of a valid format, but fundamentally there's no way to ensure that the score is "real".

<comment><USER7> No, but you can make it much more difficult by passing something like a frame of the game state, where some variables (like Timer) are passed in plaintext, and others (which are calculated in an aggregate way at runtime, e.g. can't be easily guessed) are hashed for double checking by the server. Of course double-submission is still an issue, but nonces and server-side duration checks should help you here as well. Compress the &*!# out of your source and.. it will at least take an attacker a lot of time to break.

afaict (would loved to be proven wrong here) Firebase gives you basic protection but any script kiddie will still be able to defeat it.

Edit: grammar

</comment></comment></comment></comment></comment><comment><USER8> When the floods hit Alberta, I saw a need for a realtime communications app to match volunteers with the victims who needed them. So I had a weekend project on my hands.

Without much/any javascript/web experience I was able to take their existing twitter-clone implementation and transform it into a flood relief application [http://highriver.abfloods.ca/](http://highriver.abfloods.ca/)

It never really got the traffic that I had hoped, but the whole development process went very well and I got the support from them that I needed. Thank you! I'm looking forward to their upcoming developments.

</comment><comment><USER9> I would love to see a highscalability.com article from the Firebase guys talking about how they handle the load, particularly with strategies around broadcasting X messages to Y clients who are distributed across Z servers.

(Or if anyone has links to similar discussions around scaling strategies in a messaging-heavy distributed architecture, that would be great as well!)

</comment><comment><USER10> I used FireBase to power my multiparty WebRTC video chat, and the entire codebase is < 300 lines. What is the most exciting for me is that FireBase also has an iOS and Android SDK, letting me work on mobile apps that plays nicely with my WebRTC app without having to worry about implementing a real time backend: [http://opentokrtc.heroku.com/](http://opentokrtc.heroku.com/)

The only feature I wish that firebase would have is the ability to detect when the last person has left the connection. Currently, the only way to accomplish this is with their nodeJS module.

</comment><comment><USER11> This looks good. But I do have some doubts regarding its querying abilities. As far as I can tell, you can only define a range of data to be fetched (limit). If I want to query for a particular value, i.e. fetch all users matching name - that doesn't seem possible. Or am I missing something?

<comment><USER12> It's possible, but you'll have to structure your data slightly differently. There's a blog post detailing one possible approach: [https://www.firebase.com/blog/2013-04-12-denormalizing-is- no...](https://www.firebase.com/blog/2013-04-12-denormalizing-is-normal.html)

We're working hard in regards to adding more powerful query support to Firebase though and would love your feedback so we can improve the API (just email firstname.lastname@example.com).

</comment></comment><comment><USER13> Really happy for the firebase team. Here's something that's been bugging me for a while (and why I only used firebase on pet projects rather than my main systems):

1\. How does it work with non-only web stuff such as background workers, C, Python software, etc.

2\. What about the hosting for html/css/js?

Here's a real world example:

I've got a python software that scrape an uploaded PDF for patients data and then create a kind of todo list for doctors/nurses/students. That todo list is accessible from the web - more specifically from a mobile browser. The front- end was hacked using html/css/js (angular).

I really wanted to use Firebase but struggled about the 1) and 2). It seems that the solution is to use a VPS to host a node.js back-end, but rather than using mongo it should use the firebase database through their node API, amicorrect?

For some reasons, when I thought about using firebase, I expected it to host the html/css/js files and provide the background jobs. Why can't I just have a some_task.js and call it from my js code using firebase API? I.e.

        Firebase.async('some_background_function', function (result) { .. } );

Same for hosting.. I thought of firebase more like a one-stop shop.

As you can see, I might be a bit lost so please feel free to point where I'm wrong!! : )

</comment><comment><USER14> Firebase is terrific and this is great news it's fully launched. I've talked with their founder in depth about their growth plans and I'm very impressed and excited for them.

</comment><comment><USER15> Can't rhyme the unrest over the NSA leaks with the praise for this database as a service. If this becomes popular, just plugging into one service will give secret services etcera access to _many_ websites. And since its out of your control, you're not going to find about it either.

This tale of internet surveillance is not an abstract stories with bad and good guys, it has happened through the sum of all our own practices, the way in which we have built web services, and the dependencies we construct. Lets take that into account into our daily lives as developers ( /rant )

</comment><comment><USER16> Firebase looks awesome and would be great for something I'm working on. The first thing I did was check if it was based in America then decide not to use it.

They are synchronizing your data so it's all going through their servers.

I think it's a great idea, unfortunately I won't be using it.

</comment><comment><USER17> The combination of Firebase, Angular, and Node.js is the most powerful development platform that exists today. I wouldn't build any web application without these three.

<comment><USER17> FAN for the win.

</comment></comment><comment><USER18> That's good news, but with their production version, the pricing also changed. I believe before they had more of an AWS/S3 model paying per GB stored and transferred. Now I need to pick a tier, and pay monthly.

</comment><comment><USER19> Congrats! Firebase is awesome.

<comment><USER20> Rohan! haven't seen you around in awhile!

</comment></comment><comment><USER21> Great project! :)

</comment><comment><USER22> Congratulations on arbitrarily incrementing a version number?

I really don't understand why anyone would be willing to use something like this for anything beyond a toy website. I would be very wary of using a closed source commercial database for any core infrastructure, I can't imagine a scenario where I would be willing to use any kind of 'highly proprietary database as a service'. It's vendor lock of the worst kind.

<comment><USER23> [Firebase Founder] Hi Justin, we're pretty excited about leaving beta and think it's fairly significant. Building robust infrastructure isn't an easy task and this change is meant to signal that we're ready for primetime. I hope that comes across!

If you're worried about lock-in, I'd first try Firebase along with our AngularJS[1] or Backbone[2] bindings. You don't have to change the way you write your app and can switch Firebase our for another backend easily. We recognize that we're only going to win a developer's trust by building a reliable service with the best tools and fair pricing -- so this is what we're going to do

I'd love to dispel any concerns, please feel free to email me anytime (james at firebase)

[1] [https://github.com/firebase/angularFire](https://github.com/firebase/angularFire)

[2] [https://github.com/firebase/backfire](https://github.com/firebase/backfire)

<comment><USER22> Hi James, thanks for the thoughtful reply to my grumpy trolling.

I can at least tell you what would dispel my concerns:

1\. Some kind of death-rattle clause. If your company doesn't make it or shuts down this service, all the code necessary to set up the service would be released under a permissive license, something like that.

2\. The ability, even if it had a high cost ($100k a year or something crazy), to license the source to the engine that powers Firebase and deploy a modified version (obviously just for our own use).

I think those two things would mean that if I were making decisions on the technical direction of a company or large project, I wouldn't feel like Firebase might suddenly cause a major disruption in the future. At least if there were a major incident or insurmountable problem with the service, we could bring it in house and proceed without having to go back and re-engineer all the previous work.

<comment><USER23> I've seen worse on the internet :)

To answer your questions:

1\. We put our code in escrow for very large customers. We are thinking about the best way to address the concerns of everyone else. Stay tuned.

2\. This is coming. It'll be a little while.

Thanks again for your comments. Criticism helps us figure out where we need to improve.</comment></comment></comment></comment>


Google ML/AI Comic - <AUTHOR> https://cloud.google.com/products/ai/ml-comic-1/ <comment><USER2> Annnnd Martha still doesn't have a ml-solvable business problem identified with a large enough curated dataset to actually create a useful model.

<comment><USER3> That's not a problem at all! In the fortune 500 there are plenty of companies with "problems" that used to be solved with boring things like "averages" and "business logic", but now you can replace those things with LSTMs and Deep NLP models and get half the performance with several orders of magnitude more complexity! The best part is the people building these systems have none of that annoying "engineering background" baggage that will mean they don't worry about stupid stuff like support and maintenance, or even basic debugging: if the model breaks you just build a brand new one!

<comment><USER4> As an added bonus, people with these skills cost x3 as much as a standard engineer. HR will love it!

</comment></comment></comment><comment><USER5> Comically absent in this description of ML which includes hard technology like NLP and actual use cases like self-driving cars is the elephant in the room of advertising and surveillance. It's just like Andrew Ng's machine learning course on Coursera - lists all these uses of machine learning....except mining user information for advertising and other purposes. If anything, it's buried under "image recognition" and "recommender systems". And yet it's what brings in the dough. Pretty telling that the overwhelming majority of this technology's current application is too unpalatable to acknowledge.

</comment><comment><USER6> Looks like Scott McCloud worked on this. I highly recommend his book "Understanding Comics".

<comment><USER7> It appears that it is not the first time he works with them, he also worked on their chrome comics posted elsewhere in this thread.

</comment></comment><comment><USER8> Before clicking, I wondered if this was going to be a comic produced by ML. Has such a thing been done?

<comment><USER9> I wondered exactly the same thing and scrolled to the end for the human credits:

      Script by Dylan Meconis, Scott McCloud, Syne Mitchell
      Art by Dylan Meconis
      Color by Jenn Manley Lee
      Japanese localization by Kaz Sato, Mariko Ogawa
      Produced by the Google Comics Factory (Allen Tsai, Alison Lentz, Michael Richardson)

<comment><USER10> Even GPT-2 can't create long, coherent stories; I doubt that such an AI which can explain things and draw useful pictures exists.

</comment></comment></comment><comment><USER11> [https://federated.withgoogle.com/](https://federated.withgoogle.com/) this is another fun one

</comment><comment><USER12> I'm picturing this comic as a tattered poster on the wall of an abandoned shell of a factory where the last human rebels live 200 years in the future after post-AI fallout.

<comment><AUTHOR> With a bunch of 'wanted' posters from a.d. 2026 next to it.

</comment></comment><comment><USER13> If I would have seen this five years ago, I would find it cool but it is a hard sell now. So many similar projects are around now for conveying basics of ML mixed with a pinch of fun elements.

<comment><USER14> I don't think anyone is trying to sell you anything, friend.

Learning and educating come in different shapes, sizes, flavours, and many people learn in different ways and at different paces. This is just another way others can learn about a complex topic.

</comment></comment><comment><USER15> Ah yes, the common scenario of engineers getting time-and-a-half for their overtime work.

<comment><USER16> It's a good expectation to include subtly in something that will be read by a variety of people. The Overton window on this won't be moved quickly, but it's nice to think that it might be moved...

</comment></comment><comment><USER17> Good explanation of machine learning somewhere under the layers of condescending rhetoric and marketing. I went into this expecting something like the chrome comic and boy was that underwhelming.

</comment><comment><USER18> Reminds me of Logicomix! ([https://www.amazon.com/gp/product/1596914521/](https://www.amazon.com/gp/product/1596914521/))

</comment><comment><USER19> The Chrome comic is pretty iconic I think: [https://www.google.com/googlebooks/chrome/](https://www.google.com/googlebooks/chrome/)

</comment><comment><USER20> I like this, especially since it seems to make a fair case regarding CNN and Deep Learning (not solve-alls).. looking forward to the second part.

</comment><comment> happy-go-lucky It's a great intro. It reminds me of the official scikit-learn tutorial I worked on a while ago.

</comment><comment><USER21> Mel is Bezos?</comment>


Ask HN: What is the best resource out there keeping track of great tools? - <AUTHOR> Often a friend or a client will ask how to solve a particular business problem and I will have the right tool at their disposal which I have already used and tried. But if I have not been lucky to read about that tool or having used it, I might have not easily been able to offer a solution.
I'd love to find a place which has listed 100+ tools for different problems (marketing, project management, email, cloud storage, invoicing software, you name it) that I can browse and see what problems it solves.
Does anything come to mind? And besides Product Hunt, how do you stay up to date on new tools that can help you at work? <comment><USER2> Slant[0] and StackShare[1] are probably your best bets. The former is better for desktop applications or utilties, the latter is better for frameworks and the like.

If you're looking for a specific niche, Product Hunt has a ton of curated lists that tend toward marketing/design. GitHub is probably a better source for curated lists which focus on things developers would find useful.

[0] [https://slant.co](https://slant.co)

[1] [https://stackshare.io](https://stackshare.io)

</comment><comment><USER3> Not for all problems but for some technical ones I use lovely curated awesome lists.

[https://github.com/sindresorhus/awesome](https://github.com/sindresorhus/awesome) is a good starting point.

</comment><comment><USER4> [http://alternativeto.net/](http://alternativeto.net/) is pretty good. You need to know one tool in the area you are looking for, but if you do it gives a good list of alternatives.</comment>


The TSA Randomizer App Cost $336k - <AUTHOR> https://kev.inburke.com/kevin/tsa-randomizer-app-cost-336000/?lobsters <comment><USER2> Let's assume a hefty markup for the long sales/BD time for a government contract like this: $336k * 0.60 = $200k

Since this deals with national security, could probably justify higher rate resources staffing (security clearance required?). Ballpark $250/hr @ 8 hr/day so $200k buys you 100 days of capacity.

Project breakdown:

* UI/UX Design: 10 days (lots of stakeholders+approvals needed, maybe field testing with TSA agents, accessibility audit)

* Development: 15 days (this is very conservative but might be some business rules that aren't being shared -- remote monitoring, analytics, auditing, static analysis, etc)

* Project Management: 25 days

* QA: 15 days (multiple devices, high perceived security exposure)

* Third-party security audit/pen testing: 5 days

* Technical writer for documentation and training materials: 5 days

Total: 75 days of capacity spent.

Math doesn't work out exactly and some of these numbers are pulled from thin air, but it seems like it's at least in the right ballpark.

Do you folks really know people that are doing government contract work (for the TSA no less) for less than $100k?

<comment><USER3> Yeah clearly this ui [http://elliott.org/wp- content/uploads/IMG_6317.jpg](http://elliott.org/wp- content/uploads/IMG_6317.jpg) required 10 days to design.

Why would this require more than a few days? Simple UI, then just generate a secure random number and draw an arrow. Bam. Give me 200k.

I mean the largest expense would almost certainly be third-party pen testing and QA. And why would it take a technical writer 5 days to document this? It has 1 function.

<comment><USER2> That's one screenshot, are you prepared to submit a legally binding quote for the project with that little information? Are there more screens? I don't know. Did the client require multiple designs and iterations -- each stamped with the approval of several stake-holders? I don't know.

Judging the final output without any consideration for the process is akin to asking why it took a week to fix that hairy bug. It was only one line of code that changed, how could it possible take you all week to fix it?

<comment><USER4> Sure, since, in government contracts, "legally binding quote" doesn't mean you actually start losing money or have a judgment issued against you that you're personally liable for if there are time or budget overruns.

</comment></comment></comment></comment><comment><USER5> I worked at a company that had to resell its software through a disabled, veteran-owned sole proprietorship so that the TSA could find budget to purchase it. The way it was described to me was that a portion of the budget is earmarked for these businesses, so if the primary technology purchasing budget runs out, you can still sell to the TSA if you resell through one of these businesses. Essentially, the reseller took a cut for doing nothing, and fleeced the American taxpayer for a few hundred thousand dollars. I'm sure this happens all the time.

<comment><USER6> To be fair, if the taxpayers are going to be victims of bureaucratic inefficiencies, I'd prefer that the beneficiaries be disabled veterans vs. that money going to Boeing or Raytheon or Palantir or whoever.

<comment><USER7> I still can't believe someone named a company Palantir. In Lord of the Rings, the palantíri fell into the wrong hands and were used to do literal, honest- to-god evil. It's like naming a company Death Star.

<comment><USER8> _It 's like naming a company Death Star._

Or like making a mission patch that's an octopus with its arms around the earth, with the tagline "nothing is beyond our reach"?

It's all about audience, right? Palantir used to have t-shirts that said "save the shire" on the back -- dunno if they still make those.

</comment></comment></comment></comment><comment><USER9> I've done some federal contracting and the issues seem to be cultural. The government hands out what they call "prime" contracts which are then subcontracted out to multiple other firms. The primes tend to be stodgy old companies filled with lawyers and MBAs that can win the contracts, who then view the engineers as replaceable cogs. You then interact with multiple other contractors that own particular parts of the stack, for example an independent testing contractor and another for infrastructure. It wasn't uncommon to have 5 project managers for each engineer on the project.

Coming from tech startups this was completely shocking, I was so used to an engineer driven culture. That developers couldn't write their own tests, or manage their own infra, or deploy multiple times a day was super frustrating.

There sounds like there are some great initiatives to change this old approach, but until then I can't imagine many talented devs would put up with the bureaucratic bullshit.

<comment><USER10> > That developers couldn't write their own tests, [...] was super frustrating.

I can see advantages to having someone else write tests for the developers.

And I don't see how they stop you from writing tests for personal use, if you want to.

<comment><USER11> In the aerospace industry (commercial and defense are similar here because the software for commercial has to be written according to government rules, see FAA DO-178B) it's actually verboten. Testing independence is part of the flight certification of the software if I'm not mistaken.

<comment><USER10> This has all the enforceability of prohibiting your workers from thinking about what they're working on, or practicing in their spare time.

Tests you write for your own benefit are not a deliverable. They're part of your work process.

As I said before, it's not ridiculous at all to require that _deliverable_ tests be written by some other party than the developer whose code needs to pass them.

<comment><USER12> Actually I think this is one of those things that sounds so obvious, and yet isn't right in practice.

I'l roughly segment projects into those that can fail a bit and those that can't.

Now obviously, for things that can't fail even a little you can't just take someone's word. But why can you take the word of two people, or ten? The failures (in programming and code review) are absolutely correlated. If one person fails at something another likely will fail in the same place or when reviewing it. When people die if there's a bug, or you're even losing a lot of money, you should not be trusting best-effort human _anything_. This is where imperative programming against a test suite breaks down and just can't cope. You _need_ to switch out your internals for something provable in its domain. (eg, the math to land a space shuttle in a fixed-time infrastructure (ie before it lands itself)).

And for everything else, it's a $/$ calculation. How much do you want to spend to have some unknowably smaller amount of risk? And usually the best value for the dollar is having the original engineering team work on the tests, with outside oversight and good metrics. If an integrated team is having problems getting full branch coverage (the only worthwhile coverage metric...) in a given method, they rewrite the method. External teams have to test what's given (or waste a ton of time in communication delays) and that usually ends up with suboptimal tests _and_ suboptimal coverage. What you can't do though is simply ask a developer if their work is properly tested and trust their answer. You need real metrics and to know what they mean for you. (Like benchmarks.)

<comment><USER13> The tests are written independently of the original code. If someone has made a logic error or misunderstood some part of the spec, there is a good chance that the independent test implementation is not going to have the identical error. It's definitely a higher chance of finding bugs than having 1 developer write both, as long as the testing is written independently based on an API.

<comment><USER12> There's a difference between code tests though and spec verification.

Spec verification is (should be...) black-box integration testing. And yes, this is a good chance to get a second set of eyes on the spec to make sure nothing was missed in the implementation. (unit-tests can't catch missing code!)

Code tests should be more white-box and should be measured against line/code coverage instead of spec coverage. These are what I think the original devs should write, and should be 95%+ of the total test volume.

The problem with expecting testing to pick up spec errors is that it takes comes at the end of the design/build phase instead of the beginning when you can make changes easily.

<comment><USER13> Well you're not going to pick up spec errors with same-developer unit tests, so either you have someone else write those spec tests or you wait until the customer picks them up on initial delivery / QA.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER14> "..that a beginner could build in a day.."

Yeah... the clue is that an entire bureaucracy is required before even the first line of code was written. This thing probably took months and months of meetings with tons of people before the prototype was written.

<comment><USER15> What would happen if, some fraction of the way through the long stretch of bureaucratic meetings, someone just coded a prototype?

If they sit on it and whip it out the moment the green light is given, then what?

If they whip it out at the next red-tape meeting, then what?

<comment><USER16> I can tell you what happens. I worked at a very large telco.

We went through months of daily meeting with 10+ very expensive execs, PMs and Business Primes from all over the business.

One day the only other coder in the room leaned over to me and said "Are we still talking about <x,y,z> that you or I could code in 10 minutes?"

Yes, we were.

I coded it and showed my managers and so forth. I was completely ignored, and the meetings rolled on. In a place like that, there are so many people that have job titles that have nothing to do with "getting it done", which in a funny way makes them less interested in getting it done. Their job is to analyze, plan, document, process map, etc. etc. so that's what they're going to do, no matter how trivial the thing is.

<comment><USER17> Exactly! I would argue it creates MORE red tape and work to do that, than less. I've done it, I've seen it, it actually makes your life worse, not better.

<comment><USER16> When I stopped trying to make that place better (I'm banging my head against the wall) and started just going with the flow, I knew it was time to leave.

</comment></comment></comment></comment></comment><comment><USER18> Honestly, for a custom app from one of the largest corporations (IBM), for the largest of organisations (US Govt), $336k is pretty reasonable!

<comment><USER17> Seriously. 336k is absolutely nothing. Think about how fast that gets used up adding up the numbers of the per hour of those involved, and how many people it is (not just the developer who does it)

You can argue that you don't need that many people, and certainly for a start up that's often true.

But in enterprise software, you actually do need a ton of people because of the expectation.

I'm in the Business and came from start ups. I'd VASTLY prefer to do things in small groups to just get things done.

But even though I want that, no one else does, including the customer. They want all the bells and whistles of a ton of people. It makes no sense at all.

Hell, one of my current projects has about 20 people on a phone call, and 4 that actually understand anything going on. Think about all the money wasted in all of that, and yet... It's the way business "works".

</comment></comment><comment><USER19> The $336K appears to be just the cost of one installment. The total project costed $1,444,315 Here are the rest of the transactions under the same contract: [https://www.usaspending.gov/Pages/AdvancedSearch.aspx?k=HSTS...](https://www.usaspending.gov/Pages/AdvancedSearch.aspx?k=HSTS0313JCIO494)

TSA spends most of it's budget through a provision called "Other Transaction Authority" which is essentially a vehicle to make purchases with barely any oversight from congress. [http://time.com/4134368/tsa-price-of- security/](http://time.com/4134368/tsa-price-of-security/) (Paywall)

<comment><USER20> I'm glad you brought this up, because this comment represents a misunderstanding in how government contracting is typically done. My previous job was working for a government contractor, and we did multiple discrete contracts for several branches of the government. However, _every single one of them_ would have shown up exactly like this, all bundled under one contract.

Why? Because writing and signing a contract is _expensive_ , for both the contractor and the government. So contracts are typically written in a way to make them very easy to extend, and existing contracts are often used as vehicles to tack on additional funding for new contracts. The original contracting agency would also usually charge a fee to the other agencies for use of their contract in this way.

So, this kind of glance at individual awards under a single contract is really too simple a view. A lot of these funds could be (and from my guess, probably are) going to completely independent projects from the randomizer.

TL;DR: Having multiple awards under a single contract is typically a sign of the government working _around_ bureaucracy and attempting to save costs.

<comment><USER19> Yeah -- you are correct.

TSA later reported that the actual cost of the randomizer was around $47k. The total figure I had mentioned earlier was part of a larger contract with IBM. I saw the generic "IGF::CT::IGF MOBILE APPLICATION DEVELOPMENT" note on the award and assumed it was all for the same project.

It's also weird that TSA's response to OP's FOIA request cited a different and higher figure (~$340k) for the randomizer app -- I'm guessing they were grouping in other projects under the same award here too?

Besides, $47k seems like a reasonable amount if that figure includes training and deployment costs.

</comment></comment></comment><comment><USER21> The government would be a lot more efficient if everyone who worked for them was a little more tech literate. I don't think the lack of education is entirely the US government's fault. Tech moves so insanely fast it can be a full time job just keeping up with the changes. My point being, this is not the price of building a tiny app. 336k for a randomized arrow is absolutely ridiculous. This is the price for making a change in a government run security system. A change built on technology that government officials don't fully understand.

<comment> brown9-2 This assumes all inefficiency is accidental, or done out of a lack of knowledge.

<comment><USER22> Don't attribute to malice what can be attributed to ignorance

</comment></comment></comment><comment><USER23> A few things.

1\. Kevin you may want to block out your address in the attached letter.

2\. I'm missing the part where this amount is tied directly to the creation of this application and this application only. From my read this is a T&M contract for mobile development there's nothing specific to this application. It could span multiple engagements and apps. Considering this contract went into place over 2 years ago this could likely be the case.

3\. This is a cap not an invoice. They could have billed 60k.

<comment><USER24> Some details of past IBM wins here via UsASpending: [https://www.usaspending.gov/Transparency/Pages/AwardSummary....](https://www.usaspending.gov/Transparency/Pages/AwardSummary.aspx?AwardID=17381939)

This may be the preceding contract but very similar scope and line items if you want more details, no FOIA required.

</comment></comment><comment><USER25> I suspect that one secret feature of this app is a discreet way to override the randomizer and send a passenger to the "intrusive search" lane. That is, if the screener suspects someone, he or she can swipe or click in a clandestine way to guarantee that the passenger gets the annoying search.

The passenger can't complain about being targeted or profile or singled out, because, hey, it's random.

(The actual rationale of the randomizer might have been to avoid accusations of profiling, _while still being able to do profiling_. Leaving the bad guys off balance is simply a benefit.)

</comment><comment><USER26> Notice this is also T&M (time & materials) which is not just a fixed priced bid.. so that means someone "used" the actual working hours and materials for the $336k bill.

(Contract negotiation, etc is not explicitly built into these, they're reflected in a higher billing rate.)

<comment><USER27> No, this is just the contract, which would be based on IBM's cost estimate. Since it's T&M, the actual total cost and hours will only be reflected on IBM's invoices.

</comment></comment><comment><USER28> Yo app got a $1,000,000 from Andreessen Horowitz, so they kind of got a deal if you think about it that way

</comment><comment><USER29> The PDF contract the author shares doesn't make it clear what deliverables it covers. Perhaps we can assume that if the FOIA process worked it is in fact the contract that covered that app... but it's not clear from the document itself, nor is it clear that the 'TSA Randomizer App` was the _only_ deliverable of the contract.

<comment><USER30> Yes, it was unfortunate I didn't get more data/information back from them :(

</comment></comment><comment><USER31> Before we even go into line item mode we really need to ask ourselves if this is a $336k problem in the first place. They could have just asked the military how they handle this sort of problem, and the solution they would have been given is this: a $2 hand tally counter. Establish what the desired flow rate is, divert every nth person, reset the clicker, anybody in line observed shifting position gets diverted. Unless the TSA can't even trust their people to count, or their real objective is adding some weirdly alienating layer of technology between the employee and the traveler.

<comment><USER32> "every nth person" selection is just too predictable. You could try to prevent people shifting in line, but in a crowded airport you will never be able to control that effectively at current staffing levels. The cost of effectively enforcing that rule would rapidly add up to more than $300k and cause serious inconvenience to travelers.

<comment><USER33> Yes, preventing shifting in line doesn't help if your attacker can just count the length of the line before they get in it. You really want a random element. Anyone familiar with Dungeons and Dragons should be able to name the obvious solution there....

<comment><USER34> But Mike, what good would Polymorph do in this scenario?

<comment><USER33> If you can't figure that out on your own, then you're _obviously_ unqualified to be a TSA officer.

<comment><USER34> Haha, bummer.

</comment></comment></comment></comment></comment></comment><comment><USER35> Once again, contracts are rarely for just development. It likely included design, development, deployment, testing, training, accessibility testing, analytics.

</comment><comment><USER36> They could have used a magic 8 ball with similar outcomes

<comment><USER37> Dice app that could support even 6 lanes - free.

[https://play.google.com/store/apps/details?id=tobi.wuerfel&h...](https://play.google.com/store/apps/details?id=tobi.wuerfel&hl=en) [1]

[1] Not affiliated or tested. It was the first I found without inapp purchases or ads.

<comment><USER17> But as a service it isn't controlled. What if someone took control of it, and then used it to game the system. Security is shot.

Not that I really think that matters at all, but that would be shot down in the first meeting it was discussed immediately, and you'd be considering insane if you kept pushing it.

</comment></comment></comment><comment><USER38> Couldn't find in the contract if the hardware was provisioned or not.

</comment><comment><USER39> Why is there a ?lobsters qs on the submitted url? Seems to load fine without:

[https://kev.inburke.com/kevin/tsa-randomizer-app- cost-336000...](https://kev.inburke.com/kevin/tsa-randomizer-app-cost-336000/)

<comment><USER30> I submitted it to Lobste.rs with that on the end of the URL, and someone must have submitted the URL without stripping that :)

</comment></comment><comment><USER40> If this is truly the price to develop such simple software, it's going to be very bad for the government's reputation to be releasing code like this under open source licenses.

<comment><USER41> Theyve already said they won't if there's a security or privacy risk, and you can find one of those in _any_ code.

</comment></comment><comment><USER42> No invoices against the contract? This is only part of the picture.

It's a time and materials contract which means the contract award is the "ceiling", but you have to perform work billed against it to get paid any of that.

Plus, the second page details several extension options that could increase the ceiling to $1,176,280. Were those options exercised?

<comment><USER30> We don't know; I've amended the post to reflect this. Thanks.

</comment></comment><comment><USER43> One-sided negotiation is a cost riser. The last thing a client should be able to tell is that the payer has very deep pockets; if I know you can _afford_ billions, I might ask a ridiculous price and expect you to not know any better or not care about paying it.

An excellent use of secrecy technologies would be government contracts: partition problems into pieces that don't necessarily reveal the final purpose or customer (e.g. "choose uniformly between A and B" is too vague to be guessed as a requirement from only a government agency). Then, anonymously ask for bids. That way, you might actually get the developer who offers a measly price for a trivial task, and only finds out later that his check is from the government.

</comment><comment><USER44> What is WAY worse is that they probably purchased 10,000 ipads to run this stupid app.

</comment><comment><USER45> Less worried about that and more worried about the fact that baggage scanners only scan from one angle combined with reality that they don't do material differentiation.

Z-effective scores...findable.

</comment><comment><USER46> But no one got fired for choosing IBM

<comment><USER47> I came here to say this.

<comment><USER46> Pfft! Yet another cliché slinger

</comment></comment></comment><comment><USER48> The page (2 of 8) that had the unit prices censored (exception (b)(4))[0], claims the total award amount was $1,176,280.72.

Really, what we need is IBM's invoices and TSA's pay statements.

Also, you shouldn't need to file an FOIA request to get this information. Shouldn't all bids and contracts be public?

[0] Exemption (b)(4): Records that contain trade secrets and commercial or financial information obtained from a person that is privileged or confidential.

<comment><USER17> Unit prices are trade secrets. If they published that, then someone else getting a higher price could point to it, and say they only charged X for them.

</comment></comment><comment><USER49> A coworker and I were laughing about this at the airport one day. I literally wrote the app in the flight home and almost put it up on the App Store.

</comment><comment><USER50> Ya well, that's 10K development, 30K profit and 290K meeting time and paying people to fill out forms. Sounds about right.

</comment><comment><USER51> Why does this surprise anyone? Forget an app. Just a normal computer that government buys ends up paying 1.5 of what you will get on Amazon.com. This is because government does not pay on time, there is a lengthy and resource consuming process in selling something to the government.

The app was probably $10k, rest was the compliance cost.

</comment><comment><USER37> It was 300000 for lobbying grease to land the contract, 30000 profit, 6k for hardware and 500$ for one intern to write it.

<comment><USER17> Funny but ultimately wrong.

The real distribution of where the money goes on projects is certainly funny from a sane persons perspective, but in a different way than this :)

</comment></comment><comment><USER52> Why not just have TSA agents flip a coin, or buy a bunch of Trouble board games, and repurpose the dice rolling bubble?

<comment><USER12> The trouble bubble is not only a perfect solution for this, but an apt metaphor for the whole process.

</comment></comment><comment><USER53> We're talking about the app with 1 arrow on the screen that responds to a press anywhere on the same screen? 1 icon, 1 tap target, hooked up to 1 secure random algorithm.

I don't know how anyone can look at this situation and not see the government is wasting a lot of money in their pursuit of not understand technology.

</comment><comment><USER54> Hmmm... at the current rate of bureaucratic growth, I estimate in a 100 years or so, this app (or it's modern AR equivalent) will cost 20% of the entire federal budget. No worries though, 10% of all U.S. workers will be involved in its digital-paper-pushing development.

</comment><comment><USER55> With a reference to another recent hackernews story: [https://news.ycombinator.com/item?id=11415747](https://news.ycombinator.com/item?id=11415747)

Can we expect to see the source code for this application pretty soon?

</comment><comment><USER56> It seems a bingo spinner with two colors of balls would do just as good of a job.

[https://www.google.com/search?q=bingo+spinner&tbm=isch](https://www.google.com/search?q=bingo+spinner&tbm=isch)

</comment><comment><USER57> A little bit tangential: when you go to the slower lane and they swab you with those silly machines, can they _actually_ detect anything?

<comment><USER12> fyi, this is not a time to apply science.

</comment></comment><comment><USER58> It'd be interesting to hear what do "materials" can entail. It might be that they actually delivered iPads to the airport.

</comment><comment><USER59> If this is what it seems then that is ludicrous.

</comment><comment><USER60> What I want to know is does it still work if they turn on the rotation lock and hold the iPad upside down?

</comment><comment><USER61> If you're a consultant or freelancer, and you're not charging that much to build an equivalent app, you are undercharging.

This is a completely reasonable price. Honestly, it seems cheap.

</comment><comment><USER62> random rand = new random();

int tsaNumber = rand.nextInt();</comment>


What Do You Think about This Seamless "Registering/Login" User Experience? - <AUTHOR> https://community.vanila.io/uiux/general/what-do-you-think-about-this-seamless-registering-login-user-experience~cd5aeb82-8d13-46ed-b099-2b8865443a66 <comment><USER2> I find it to be intrusive and disturbing. Medium.com does this and I've always hated it.

Mediums usage of it actually caused me to switch, on my work computer, from always being logged into Google, to never being logged into my Google account. Now if I have to use one of my companies apps that requires a Google login, I do it incognito.

At home, I never browse while logged in, so I didn't ever notice it that much. Using my Google account for logging into a third party web application is never my first choice. I'll take separate email / passwords for everybody please and thank you.

<comment><USER3> God, Medium has the worst login experience of any site I use. What makes them think they are too clever to be usable with a password manager like the rest of the damn internet? I usually just reopen the article in an incognito tab instead of going through their stupid "send me an email!" bullshit login.

<comment><USER4> For every user like you who is using unique, securely generated passwords in a manager, there's 10,000 people who are using the same, easily compromised password on every website they're registered on.

You're not the target audience for these features - not only are you the tiny minority, but no matter what system they give you, you'll find a way to interact with it safely, so for that interaction you simply don't matter.

And choosing to do this kind of login pushes blame for authentication issues away from that company, and onto the federated provider, who presumably has legions of security researchers to make sure they're doing things safely.

<comment><USER5> Huh, new idea, Google already prompts me on my phone when I log in to Google on a new device, why isn't there a service where instead of having to open my email and find that darned Medium email, it can push a question to one of my devices (also on PC) and I can just press "Yes that was me, let me in"? It can be some third party so I don't need a different software for each site..

<comment><USER6> Isn't that basically logging in with Google? I mean Google isn't asking you if you logged into Medium with a push but by the time you're doing that Google already knows it's you and pushed you a notification to log you in initially.

<comment><USER5> Almost, but what if I'm uncomfortable with Medium having my real name and profile pic (which Google's SSO will share)?

I'd imagine Medium would offer "authentication through X", and I can either enter my id for X, or go to the X app and generate a new ID for use for Medium, and paste it on Medium. So next time I want to login to Medium, after entering my username, Medium's backend talks to X's backend (saying user with this ID wishes to login) X can prompt me on one of my devices. Medium can display a unique number on their page for me, and I can compare that to the number my X app is showing me to confirm it's me I'm letting myself in.

This is a 1 minute concept without considering creative ways it can be attacked. But I guess there wouldn't be any money to be made...

</comment></comment></comment></comment></comment></comment><comment><USER7> This really disturbs me. What's the security model for this?

Even if the site never learns my Google identity, I hate having to close the signup window. If I misclick, they get my identity. It's so sick.

<comment><USER8> I think it's probably the same as it ever was. By my read this is essentially Google releasing an iframe (or whatever) version of their "allow blorbulax.com?" page with the message reworded and combined with the "yes" button.

</comment></comment><comment><USER9> Hate it.... I do not want a site to have access to my information before I even open an account... even if that's just some anonymized ID created for the task.

Ironically, you must sign in with a social media account( facebook / twitter ) or google / github to even use this site..... Single Sign On crap just leads to your whole life getting hacked if something happens. if I cannot setup an account with a unique email address and password, I will leave.

</comment><comment><USER10> I've seen these before; it feels way too intrusive and out of place on the page. If I'd clicked a "sign in with Google" button, then okay fine, but a big dialog covering the corner of the page? No thanks.

Checking out that page, the traditional signup button (which is what I'd use as I'd rather not use Google login) is actually _under_ that dialog. You can't see it until you dismiss the dialog.

</comment><comment><USER11> I see one like this on other sites - eg Instagram. Hate it.

Don't assume I want to give you my identity.

But! Make it super easy for me to act when I decide.

These force-auth types are over-reaching and intrusive. They cause pain to the power-user and cause incidental harm to the standard-user (and maybe more)

<comment><USER8> Heck, I don't like it also because I don't want to give _Google_ the data they'll slurp from this connection.

Not for free, anyway.

</comment></comment><comment><USER12> EDIT: I misread the OP. I was under the impression that the popup came after clicking "Log in," rather than just being immediately shown on load. Ignore my comment.

Personally, I like it, and I think that from the typical user's perspective, it can probably be more convenient.

At least, it's more convenient than the classical "click a login link, which takes you to another page, try to remember your password, maybe hit I forgot and have to view your email, and then hope the site takes you back to the page you were originally on" flow. A big win is not having to leave the content you're currently viewing, which is an annoyance on mobile.

A lot of the comments on this thread strike me as cynical, and are dismissing the user experience aspect of something like this. Especially considering that the average user doesn't have a password manager (I could be wrong on this claim, I don't have a source ATM).

EDIT: I should clarify that I'm talking about the "quick sign in" pattern in general, not necessarily about any specific auth provider.

P.S. If you're trying to produce a similar flow on your site, the Credential Manager API (navigator.credentials) allows you save user credentials locally, so when they visit your site, their browser can automatically sign them in.

</comment><comment><USER13> I don't like it. I makes me feel that a miss-tap will cause me to send my details to a site

<comment><USER14> > It makes me feel that a miss-tap will cause me to send my details to a site

This reminds me of one time when I logged in to Chrome and misclicked on the dialog that asked whether to sync data. I very quickly went to settings and disabled sync, but I have a feeling Google got all my bookmarks and history and saved passwords.

That's what finally made me delete Chrome (I had already been using Firefox primarily but now have Falkon (WebKit-based KDE browser) instead of Chrome).

Very malicious how the option to keep your information to yourself is gated behind many opt-outs but if you accidentally opt-in once they take everything.

</comment></comment><comment><USER15> Given that this is a website for medical use, I'm surprised they are allowing account creation with google oauth. I'm 95% sure it's not HIPAA compliant.

<comment><USER16> [https://cloud.google.com/security/compliance/hipaa/identity-...](https://cloud.google.com/security/compliance/hipaa/identity- platform) \- looks like, at least for Cloud Identity (for employees accessing the internal records and databases themselves) - it's HIPPA compliant when the people implementing it do their DD. Since GSuite and Gmail logins are fairly tightly integrated, I would bet the regular auth system and oauth system for Google accounts is HIPPA-complaint.

<comment><USER15> If you are using a service like google oauth you need to sign a business associate agreement with them before using any of their services in a HIPAA compliant manner. I've searched for how to sign this contract pretty unsuccessfully.

</comment></comment></comment><comment><USER17> How about: forgot what email I used for a particular website, so try and login (not register!) with one of them...oops it was the wrong one but I now have an account apparently along with welcome emails to match. I am very caution about putting an email into any login form without double checking it is the right one.

<comment><USER18> I guess you know if you see the "continue as xxx" confirmation?

<comment><USER17> I have noticed many lately that don't even do that. Its auto account creation upon invalid login.

</comment></comment></comment><comment><USER19> My prediction: People on HN will hate it, the general public loves it.

</comment><comment><USER20> A big no no for me. Seen a couple of sites and never tried clicking. I'd rather use the 'sign in with google' button where I get to confirm rather this privacy insensitive method.

</comment><comment><USER21> It's probably using google oauth SDK [https://developers.google.com/identity/protocols/OAuth2UserA...](https://developers.google.com/identity/protocols/OAuth2UserAgent#example) (there's no popup raised if you're already signed in google). You can then send and validate the token on server-side, and create an account there

</comment><comment><USER22> i find this creepy. "why does this website know my name"

</comment><comment><USER23> I saw this on Zillow and I tracked it down to [https://github.com/openid/OpenYOLO-Web](https://github.com/openid/OpenYOLO- Web) or some similar implementation of that protocol. I haven't looked into it yet but I've been intending to figure out how it works and I was surprised I haven't read about it yet anywhere.

<comment><USER16> Yes -

[https://github.com/zapier/google-yolo- inline](https://github.com/zapier/google-yolo-inline)

But it seems the page for one tap - [https://developers.google.com/identity/one- tap/web/](https://developers.google.com/identity/one-tap/web/) \- is no longer a thing; the the only solution for "web" experiences is the "sign in/continue with google" javascript client that does the pop-up, eg. [https://doodle.com/login](https://doodle.com/login).

<comment><USER24> They discontinued the other one because someone demonstrated that you could hide it under another element and trick people into clicking on it

</comment></comment></comment><comment><USER25> This button allows Google to know the fact that I'm currently on this specific website. If more and more websites implement this button, Google will have access to my complete browsing history!

IMO a website must ask for a permission before displaying this button.

Facebook also has a similar button ("Continue with {my_name}") that use the same iframe method.

<comment><USER5> Well FB (and Twitter) already have "Like this page" or "Tweet about this" embeds, and those allow them to track you across the Internet (or at least on sites with those buttons).

</comment></comment><comment><USER26> hhm, how did they do that? I thought the google oauth flow required that it redirect to a google page (and show the info/permission the oauth flow is asking for).

Unless there's a security leak somewhere in cookies, which exposed your email address to this site (which doesn't belong to google i presume).

<comment><USER27> Probably iframes

</comment></comment><comment><USER28> The first time this happened to me, I instinctively clicked to login thinking Chrome was trying to log me into Gmail or my Google Account. I didn't realize I was giving info to some random site, I was just trying to swat away a popup.

</comment><comment><USER29> Seeing this on a site would instantly remove any desire I had to make an account.

</comment><comment><USER30> Something marginally less seamless: try to sign-in to google play console with a user that is not the one currently "syncing" in chrome.

</comment><comment><USER31> Well, as a user I love it.

In the other hand, as a conscious consumer, I absolutely hate giving even more information to Google.

It would be cool to have an open source, non-profit organization to work as an universally accepted authentication provider platform. One can always dream.

</comment><comment><USER32> It's insecure too :)

[https://blog.innerht.ml/google-yolo/](https://blog.innerht.ml/google-yolo/)

</comment><comment><USER33> Creating a persistent public online identity on an untrusted service at the click of a misleading button? What could possibly go wrong?

</comment><comment><USER34> gee, it is 2019 and we still haven't solved registration/sign in ;)

</comment><comment><USER35> It's a suction pump for the onboarding funnel. It is not your friend.

</comment><comment><USER36> This is world wide surveillance gone mad.

I try to avoid using creepy websites like this.

</comment><comment><USER37> interesting ... I wonder how this is secured from attacks from the website itself redressing it and/or clickjacking attacks</comment>


Jury Orders Washington to Pay Wrongfully Convicted Man $16.65M - <AUTHOR> http://www.nytimes.com/2015/11/21/us/jury-orders-washington-to-pay-wrongfully-convicted-man-16-65-million.html <comment><USER2> I would like to see settlements of this sort for wrongful arrest. Police can arrest persons without stating the reason why, and come up with the reason at a later time. The person can be released if the police don't have enough evidence to prosecute, or even charge, the person. In fact, the police can arrest you, for which you'll have a record now, and never even intend to charge you. By this point the harm is already done, and the burden is placed on the individual to have the arrest record expunged from their record; more or less presumed guilty. Many people this tactic of harassment is used with do not have the resources or sophistication to do this. Their record now makes it more difficult or impossible to get a job or receive public benefits. They are in essence being punished without ever receiving the benefit of the justice system.</comment>


California's Love of Cars Is Fueling Its Housing Crisis - <AUTHOR> https://www.bloomberg.com/view/articles/2018-03-06/california-parking-regulations-are-a-big-part-of-its-housing-crisis <comment><USER2> I think required parking spaces is a minor factor in why building is so hard in California. The biggest problem is that if you have plans for a building that meets all the existing zoning and building regulations for the lot, it can still take many years (sometime decades) before one will be able to start construction. One has to deal with lawsuits by people who don't want it built, planning commissions that have to put their own stamp on the building, and public meeting after public meeting that resolve nothing.

I have heard of a few different laws floated in Sacramento to help try and help with this problem, but I think it is more of a cultural value in many parts of California (like prop 13) where people feel a place should not change from how they found it when they moved to California. This is probably not something that can be legislated away.

<comment><USER3> Reminds me of this story:

[https://reason.com/blog/2018/02/21/san-francisco-man-has- spe...](https://reason.com/blog/2018/02/21/san-francisco-man-has- spent-4-years-1-mi)

</comment></comment><comment><AUTHOR> This is an underrated problem and also contributes to some grimly hilarious public policies that offer funding to build housing for the homeless on the one hand, but forbid most housing from actually being built on the other: [http://seliger.com/2017/08/30/l-digs-hole-slowly- economics-f...](http://seliger.com/2017/08/30/l-digs-hole-slowly-economics- fills-back-proposition-hhh-facilities-program)

</comment><comment><USER4> This is one of many many regulations and requirements that make housing so damn expensive. When you combine all these overburdening regulations together, the result is: you can't have cost effective housing anymore. At the very least they should open up a few square miles of space where they relax some or all the regulations a bit. This would allow developers to innovate and drive down the cost of housing.

We haven't seen much meaningful innovation in housing in the last 100 years, at least none that addresses cost.

Imagine what a great world we could live in, if everyone could build what they wanted as easily as building a website. There's a lot of issues to tackle, i know, but it's a good starting point for progress. And considering that most of our incomes go to housing, it's the most important area for progress.

</comment><comment><USER5> $27,000 / parking spot? I like how the total cost of the building or percentage of total cost is suspiciously lacking.

</comment><comment><USER6> It's a shame that people want to turn los angeles into nyc or sf. We have that already. Can't LA remain unique?

<comment><USER3> Uniquely filled with homeless and skyrocketing rents because there's not enough housing? Uniquely stuck in traffic because there's not enough metro lines? Unique that there's few walkable areas like the lovely cities in Europe?

No LA currently is the worst of both worlds, an unwalkable, undrivable suburb as far as the eye can see. The best thing that could happen to it is to become a real city.

<comment><USER7> Doesn't the earthquake risk significantly curb LA's ability to build up as much as NYC? I think there are probably certain density limiting factors like this. Which just means that they need to adapt to what that means in terms of sprawl and moving people around.

<comment><USER8> Very tall buildings can actually be safer than shorter buildings, because they are all made of steel, and can have a lot of anti earthquake support built in.

Also as a short proof, Japan and Taiwan are also directly on top of a fault line. Taipei and Tokyo have some of the tallest buildings in the world. The tech is there.</comment></comment></comment></comment>


Steve Jobs is Alive - <AUTHOR> http://stevejobsmonitor.com/

<comment><USER2> but this site isn't, apparently.

</comment><comment><USER3> was this inspired by this: <http://news.ycombinator.com/item?id=2979655>

<comment><AUTHOR> I guess, that and few other false stories floating around.</comment></comment>


Why do so many people embrace the Pacific Garbage Cleanup nonsense? - <AUTHOR> https://andrewgelman.com/2018/09/17/why-oh-why-do-so-many-people-embrace-the-pacific-garbage-cleanup-nonsense-i-have-a-theory/ <comment><USER2> This makes me wonder, do garbage collectors properly garbage collect themselves?</comment>


Microsoft said to block ability to boot straight to desktop in Windows 8 - <AUTHOR> http://www.zdnet.com/microsoft-said-to-block-ability-to-boot-straight-to-desktop-in-windows-8-7000002219/ <comment><USER2> What would be utterly hilarious is if the people internally at Microsoft were all using it with the "boot to desktop" setting turned on right up until RTM, ensuring they got no dogfooding of the Metro experience.

Because that's exactly what happened with Vista. Both the secure desktop switching and Aero desktop were turned off by default on both internal builds and those installed from the IT servers up until the final RTM version was released. And so they got no internal dogfood or complaints, other than from the testers...

<comment><USER3> Sorry - Don't you mean "Windows 8 style UI experience" ?

... I Hope they are trying to lower expectations so we're all blown away by how good Windows 8 really is compared to all the bad press. Either that or their own koolaid has gotten much much sweeter.</comment></comment>


Comcast memo on viral cancellation call - <AUTHOR> http://consumerist.com/2014/07/21/comcast-memo-rep-from-painful-retention-call-was-doing-what-we-trained-him-to-do/

<comment><USER2> You know, Comcast, if you didn't spend so much effort on trying to retain customers with passive-aggressive hostilities you wouldn't have to train and hire retention employees or waste time in meetings discussing why your corporation gets so much bad press.

You should just mail off a "new service coupon" that expires in 30-days for the disconnected location for the next resident instead. Someone who has had a fight to disconnect your service is _never_ going to connect your service at a new location if they could help it because of that bitter memory.

The most important job your disconnect people have is authenticating and authorizing disconnects to prevent people from being denied service by unauthorized requests.</comment>


The Synapse Memory Doctrine Threatened? - <AUTHOR> http://blogs.discovermagazine.com/neuroskeptic/2014/12/27/synapse-memory-doctrine-threatened/#hntest3

<comment><USER2> Followup experiments with more than two neurons should be interesting, to see whether graph arc destinations are remembered, or just the total.

A far-fetched mechanism could be that each neuron transmits a signature (UID), that we've not detected because we've not been looking for it (perhaps it's slower than expected, taking hours to transmit it once...). It could include gross addressing information, based on chemical gradients at the time of its formation.

I'm partial to the idea that neurons use more than just synaptic connections. It just seems too simple, especially when there's all that powerful cellular machinary (e.g. RNA transcription) just lying around...

</comment><comment><USER3> This is certainly interesting but it doesn't look conclusive

</comment><comment><USER4> How will this impact research into artificial neural nets?

<comment><USER5> Artificial neural networks are very distant from actual neuroscience. Researchers try to make their nets more "brain-like" but it rarely results in better algorithms. In the end they just use whatever works, and that happens to involve a lot of algorithms which are "biologically implausible". I.e. things that the brain couldn't physically do even if it wanted to.

E.g. sharing learned weights between different parts of the net is extremely effective, but probably not possible in actual physical neurons. Even the main algorithm used to train NNs, backpropagation, is considered biologically implausible. Although a lot of theories exist as to how neurons could implement very similar algorithms.

<comment><USER4> I think that gasnet neural networks that took into account the locally inhibitive? impact of nitrous oxide are far superior to traditional ANN. But I just read that recently, so maybe misunderstood that.

</comment></comment></comment><comment><USER6> _To put it another way, while it's easy to see how a neuron could 'store' a scalar variable using epigenetics, it's much harder to imagine that it could store a vector of values._

Of course a vector is just a scalar in disguise. Take Gödel numbering and you can store anything, even if all you have is unary coding.

Given the complexity of the _genetic code_ , why would we just consider this implausible from the outset?

<comment><USER7> Depends on your system of computation. If all you can do to your numbers is add, multiply, but you don't have a eg a floor function, you can't do Goedel numbering.</comment></comment>


Ask HN: Anyone want to start a webring? - <AUTHOR> I usually post to Medium, mostly project write ups and miscellaneous tech thoughts. I've liked it because it has a clean look and can help drive some traffic to your posts.
But Medium seems like it's taken a nosedive. Regardless of what I actually read, my feed is this political doomsday hellscape that predicts America breaking into civil war sometime today. Really not what I'm going for.
So I want to just self-host a blog, but I'll kind of miss the serendipitous reads. I'll likely be writing for no one.
Would there be an interest in a modern webring? Like a JS snippet that forwards you to other self-hosted blogs? I haven't found a modern implementation.
Thinking a maker/project sharing/misc tech theme. <comment><USER2> I've been meaning to get into more writing. I've always been fascinated with creating tutorials, so maybe I would like to write about the music program, Reason.

Would this make any sense as a part of your network?

..

Something I found on hackernews a while back, [https://blot.im](https://blot.im)

Has the clean minimal look you might be going for.

<comment><AUTHOR> Cool! I always loved Reason.

Probably! My approach to start would probably be to just add anything that roughly fits the maker/creative theme.

<comment><USER2> How should we organize?

</comment></comment></comment><comment><USER3> I loved getting lost in webrings. I'm not sure I have much to write about but know that if there were a modern implementation it would be used.</comment>


How do you make a case for Django [or Ruby on Rails] to non-technical clients. - <AUTHOR>

Businessmen typically want a web application developed. They are aware of .net or J2EE by names, without much knowledge about either.
Altho' Rails and Django offer for a much better and faster development stack, it is a big task to convince businessmen to use these platforms.
The task begins with introducing Django (or Rails), quoting some blog/research. Then making a case for the use of the framework for the specific project.
Lot of the task is repetitive. What are the sources/blogs/whitepapers and other materials you use to make a case for django (or Rails)
Don't you think there should be a common brochure developed that many development agencies could use to make the same case, over and again. Are there any such ones, now?
There seems to be enough discussion on Django vs Rails. Whereas the need is (Django and Rails) vs (.net and J2EE), at least so, while making a business case. Both represent a faster pragmatic web development in a dynamic language.
Corporates have a lot of investment in old frameworks, way due to legacy code and resources. They may have to use Java, or even Cobol. But a end user need not. How do do U get him to understand it? <comment><USER2> Well, you don't go to a surgeon and make him explain why he has to use the tools he uses.

If I'm hired as an outside consultant in my area, I don't take a new project unless it uses the tools that I think will minimize risk. It's better to reject the micromanaging client, who doesn't know shit about your field, than to accept the offer, fail, and screw up your reputation.

Luckily, so far there was only one client who tried to force me to use blocks of modems instead of scaling Skype addins. He also wanted me to work for free for first several weeks. Needless to say, I didn't continue the conversation after two strikes.

This principle also applies to RoR/Django vs J2EE. If you are an expert, you get to make decisions.

If they have legacy code written that's a completely different story, of course.

</comment><comment><USER3> Are they really up for finding out why Ruby on Rails(or Django) may be better in their case? Do they have the stomach to sit through a technical presentation highlighting why newer, faster way of doing things might be better for them?? I saw this video recently and let them have a look at it. What is it? Its the presentation explaning the reasons why YellowPages.com got rewritten in Rails. Here's the link: <http://www.infoq.com/presentations/straw-yellowpages></comment>


Formal Business Plan?  - <AUTHOR>

I am working on startup and at the moment it's at the very early stages (hacking away coding trying to get the product developed).
When (if you ever) did you have formal business plan?
Was it useful to spend a lot of time on? How did you use it? Was it worth it?
What stage if your start-up currently? (this is as a reference point) <comment><USER2> VentureHacks is a great resource for this. <http://venturehacks.com/articles/plans-ndas-traction>

</comment><comment><USER3> It really depends, if you are bootstraped, then you really don't need one. If you want to get funded, then it depends on vc or angel.</comment>


Gravity assist maneuvers in space - <AUTHOR> https://jatan.space/daring-gravity-assist-maneuvers/ <comment> chupa-chups Nice article. For even more information regarding gravity assists (and related effects like the Oberth effect) I found these articles in my comfort zone between too much detail and too superficial:

[https://aapt.scitation.org/doi/full/10.1119/1.2341882](https://aapt.scitation.org/doi/full/10.1119/1.2341882) \- sorry, just learnt this is not an open access article

[https://aapt.scitation.org/doi/full/10.1119/1.5126818](https://aapt.scitation.org/doi/full/10.1119/1.5126818) (Oberth Effect)

<comment><USER2> > _sorry, just learnt this is not an open access article_

There is no such thing as "not open access article".

[https://sci-hub.se/https://doi.org/10.1119/1.2341882](https://sci- hub.se/https://doi.org/10.1119/1.2341882)

(With a big thank you to Alexandra Elbakyan.)

</comment></comment><comment><USER3> For fans of the "Rich Purnell Maneuver" from The Martian, check out the NASA paper: [https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201500...](https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150019662.pdf)

</comment><comment><USER4> relevant scott manley

[https://www.youtube.com/watch?v=sF8roW6Cxm0](https://www.youtube.com/watch?v=sF8roW6Cxm0)

<comment><USER5> KSP taught me more about orbital maneuvers than I expected when I bought it.

</comment></comment><comment><USER6> I find it hard to get my head around gravity assists. Whatever energy you may be gaining from approaching a planet should be lost once you leave the planet. What am i missing?

<comment><USER7> As well as the wrecking ball analogy there's a second effect: if you fall in with one mass but emerge with a lighter mass, and energy is conserved, you'll come out faster. So how do you lose mass at the bottom of the gravity well? Burn some fuel!

Another good reason to burn fuel at the bottom of the gravity well is that it's more efficient to eject rocket gas when you are moving faster. Burning and ejecting gas gives it energy (the exhaust velocity from your chemical reaction) but if you do so while moving forward at the same velocity, you effectively leave the exhaust gas behind you standing still with respect to the universe, which is maximally efficient.

Put another way: if you propel yourself through deep space by throwing bricks behind you at 30mph, then this method of propulsion becomes most efficient at 30mph. Each brick you throw backwards ends up standing still, as you sail off at what is now 30.1mph.

(Presumably it's only inefficient to burn fuel when you are moving slower than exhaust velocity, and not if you are moving at or faster than exhaust velocity?)

<comment><USER8> > _if you fall in with one mass but emerge with a lighter mass, and energy is > conserved, you'll come out faster._

It doesn't work that way. If a body loses mass, it loses also kinetic energy that mass was carrying. To make losing mass helpful for acceleration, the mass must be given high enough momentum, i.e. fuel must be burned, not just ejected.

> _if you do so while moving forward at the same velocity, you effectively > leave the exhaust gas behind you standing still with respect to the > universe, which is maximally efficient._

That standing still happens only at one instant of an idealized scenario. It is not the maximum fuel efficiency either. When the rocket accelerates past that point, it gets faster and the fuel efficiency becomes even better. The higher the speed, the better the fuel efficiency (because the same rocket motor force acts on a faster body, generating more kinetic energy per second).

</comment></comment></comment><comment><USER9> _Rosetta would be in Mars' shadow, having to rely on the limited battery supply instead of solar panels. The risk was that the batteries weren't designed for the task._

Huh? This implies a change in mission parameters or doubt whether the engineering was adequate. The link in that sentence doesn't mention either. Just that the craft entered a "sleep" mode to conserve power. I expect the power subsystem was designed _specifically_ for the task.

<comment><USER10> Interestingly, that's apparently not quite correct. From the ESA link in the article:

> Rosetta's original trajectory and engineering design did not include an > eclipse, but unavoidable launch delays forced the trajectory to be > replanned. Mission controllers working on Rosetta have spent months > carefully planning and testing a low-power configuration which will allow > the spacecraft to safely operate on batteries.

<comment><USER9> That explains it. I missed that bit in the link, thanks for correcting me!

<comment><USER10> Figured it was something like that :)

No way everyone can click through every link in every article they read. Glad we were jointly able to bring something interesting from the article to people's attention.

</comment></comment></comment></comment><comment><USER11> I am just amused at all the gravity assist loop de loops portrayed in The Expanse. That seems to take just 10 minutes at a time...

At any rate I suppose computers in the future can calculate these multiples of assist trajectories on the fly...

<comment><USER12> The executive producer actually wrote a post after the episode in Season 2 as a bit of an explanation/apology for how it ended up that way, which I thought was a nice touch: [http://www.danielabraham.com/2017/04/04/guest-post-losing- sc...](http://www.danielabraham.com/2017/04/04/guest-post-losing-science- drama-finding-drama-science/)</comment></comment>


Training YOLOv4 on a Custom Dataset - <AUTHOR> https://blog.roboflow.ai/training-yolov4-on-a-custom-dataset/ <comment><AUTHOR> YOLOv4 was published[1] on April 23 with COCO weights, but there haven't yet been resources on how to adapt its architecture to your own domain. This post walks through setting up Darknet and training on a custom dataset in Colab.

FWIW, in our tests, we saw the highest mAP (89.5) on a new task[2] compared to EfficientDet and YOLOv3.

[1] [https://arxiv.org/abs/2004.10934](https://arxiv.org/abs/2004.10934) [2] [https://public.roboflow.ai/object- detection/bccd](https://public.roboflow.ai/object-detection/bccd)</comment>


How to Respond to COVID-19 - <AUTHOR> https://www.gatesnotes.com/Health/How-to-respond-to-COVID-19 <comment><USER2> This has been reposted with lengthier discussion. [1]

[1]: [https://news.ycombinator.com/item?id=22448747](https://news.ycombinator.com/item?id=22448747)</comment>