The Tether Conundrum: a look into a suspicious cryptocurrency - <AUTHOR> https://tonyarcieri.com/the-tether-conundrum <comment><USER2> 4 statements of fact that are not in dispute.

1) Tether is supposed to be backed 1:1 by USD.

2) There are now $1.7 Billion in tehters outstanding

3) They were turned down by all reputable banks they approached.

4) They have printed $450 million of tethers in the past week

[https://coinmarketcap.com/currencies/tether/historical- data/...](https://coinmarketcap.com/currencies/tether/historical- data/?start=20170119&end=20180119)

Just ask yourself honestly..... do you really believe that there is a reputable bank anywhere in the world that would allow them to hold $1.7 Billion in an account and additionally make a deposit of $450 million in a single week?

Ocams razor says this can't possibly be true.

<comment><USER3> the most charitable explanation I've heard is that tether is backed by $2 billion in value of bitcoin.

<comment><USER4> If that were true, they would print Tether when BTC price climbs, and perhaps get rid of Tether when the BTC price falls.

What happened instead was that they printed more Tether (450MM) when the bitcoin price was collapsing.

<comment><USER5> They could be printing tether when BTC collapses to allow themselves to buy more BTC to try to pump it back up. This would make it in essence backed by BTC since it's what they are holding.

</comment></comment></comment></comment><comment><USER6> There's alternative explanations for a lot of the very strong accusations made against Tether.

People always refer to Tether 'printing money out of thin air', but they never consider the prospect that investors are wiring money to exchanges, having Tether printed for their use, and then using that USDT to purchase cryptocurrencies.

Bitfinex is huge. Bitfinex also has an OTC counter, which has been known to broker trades in excess of 10-50M USD. USDT is often the medium for which these trades are executed, so it makes sense that a lot of Tether needs to be printed when BTC is crashing, as that's when the larger players decide to buy in the most.

There is a lack of transparency, and I wouldn't be surprised if things don't look perfect behind the scenes, but that doesn't mean the entire thing is a billion dollar scam conspiracy that the largest exchanges are all in on. Not all transparency is in the users' advantage in this area either. Do you know why Bitfinex doesn't tell you exactly where their servers and wallets are located? Probably because they hold over a billion USD in BTC in a single address.

Keep in mind that the market clearly values Tether at around $1USD, almost always. That's a good sign that the market as a whole does not think Tether is going to suddenly collapse and take the entire ecosystem into it at any point in time.

It's important to read criticism like this and consider it, but not believe it blindly. There are a lot of feasible middleground scenarios between "is a complete fraud and scam" and the exact opposite.

<comment><USER7> In all seriousness, who needs USDT when you (supposedly) got USD? Who would wire millions of actual USD to buy USDT to buy other coins?

<comment><USER8> Money Laundering?

You have $1M in dirty money. Wire it to Tether for some Tethers. Go on Bitfinex and buy lots of bitcoin. Transfer the bitcoin to a legitimate exchange. Sell for clean USD.

This could be a very valuable (and lucrative) service in certain circles, I have no doubt. One thing that could jeopardize the livelihood (...and lives?) of people running a business in this space would be a steeply falling Bitcoin price. They would probably do anything to keep the price up. Like issuing more magic tethers and buying Bitcoin with them.

<comment><USER7> But even then...

Why USD -> USDT -> BTC -> USD?

Why not USD -> BTC -> BTC -> BTC -> USD?

What does the extra layer of USDT really add legally, except for some added obfuscation that a few extra "intra-bitcoin" transactions would add as well?

(Genuine question, this is one of the more fascinating stories I've heard in a while :-)

<comment><USER9> It's my understanding that Tether transactions aren't traceable because there isn't a public blockchain...and possibly not even a blockchain at all. So the obfuscating step is the USD->USDT transaction. The rest of the process is getting clean money back.

<comment><USER7> Tether is on Omni layer. Its transactions are registered on the Bitcoin blockchain and I think that makes it traceable.

USD -> USDT and back is traceable using standard investigations of books and banking transcripts of entities dealing with Tether's managers.

Also, Tether is by now an internet-wide phenomenon. It's in the spotlight. And yet it keeps growing.

</comment></comment></comment></comment></comment></comment><comment><USER10> This is a pretty good primer of what looks to be the most obvious scam in cryptocurrencies (of which there is plenty of competition!). It seems to be the glue holding the market together and has rapidly gained scale. When the scam crumbles it is going to be epic and tons of exchanges are going to go with it.

In the meantime (if you like gambling), wait for another big down day and watch for Tether issues. The market will start to climb shortly afterwards. Just make sure you're playing with USD and not USDT!

</comment><comment><USER11> Why did this get flagged as a dupe? This particular article hasn't been linked yet, and it seems to have more substance and analysis than the other two posts today.

<comment><USER12> It's not exactly a dupe but it sure looks like this article just reworded a bunch of Bitfinexed posts. Why not submit the original?

<comment><USER4> Which Bitfinexed posts?

This one added something that I hadn't seen previously, which was Tether's behavior during the recent "crash."

<comment><USER12> All of them?

[https://twitter.com/Bitfinexed/status/953398351889944576](https://twitter.com/Bitfinexed/status/953398351889944576)

</comment></comment></comment></comment><comment><USER13> How about this theory: I can print USDT (by fiat) and buy BTC with it. Now I have a large amount of BTC and propped up price. Then CME starts trading BTC futures against real USD, coincidentally the trading starts at the very top of BTC price. Then I start selling both BTC for dollars AND BTC futures again for dollars (cash settled on expiry). I am making real USD and only started with USDT (supposedly backed by nothing, best case by my BTC wallet). Now that prices are 50% lower and I have tons of USD (or just print more USDT) I can start buying again keeping the price acceptable and ready for another pump before I start selling the next BTC futures contract.

Is this possible. Am I missing something?

</comment><comment><USER4> I'm a believer that Tether is incredibly sketchy, but there's one thing I don't quite understand.

Can anyone explain why Tether's price never drops significantly below a dollar?

<comment><USER14> Nominally I'd think it's because they can, theoretically, be exchanged for $1 USD. Practically that's not possible currently (by the sounds of it), but it's the same reason people don't go around selling $1 USD bills for $0.90 USD.

<comment><USER4> But that hasn't actually been true since April. Are investors ~100% confident that it will be exchangeable again in the future?

<comment><USER15> Perhaps people aren't rational all the time.

[https://en.wikipedia.org/wiki/Confirmation_bias#Persistence_...](https://en.wikipedia.org/wiki/Confirmation_bias#Persistence_of_discredited_beliefs)

</comment></comment></comment></comment><comment><USER16> Some relevant info for those of you looking into it. I heard that back in 2016 tether ran out of capital and basically the assets and IP sold to a bunch of folks under some pretty bad circumstances, and most of the core team and early investors got screwed. The buyers seemed pretty shifty.

<comment><USER16> Before you ask, I learned this through one of the engineers who worked on it. He was a good guy and pretty standup. My point was only that the people who started it are no longer the people running it.

<comment><USER17> > _He was a good guy and pretty standup_

Then he should file a complaint with the regulators. Knowingly participating in and profiting from a fraud isn't something good, or simply law-abiding, people do. Absent such a report, you are posting unsubstantiated rumours.

<comment><USER16> I'm not sure what there was to report? My opinion was that the people working on it seemed legit up to that point, but it ran out of money and sold to a set of people who didn't care about the orginal team and more or less got rid of them. There is nothing wrong with that. But would you get rid of the people who built the sophsticated operation you just bought? That seemed questionable.

</comment></comment></comment></comment><comment><USER18> I've seriously considered making a cryptocurrency backed by something.

The problem is when it changes value and fees are taken. The math can get pretty insane when taxes between the crypto organization are taken and users realize their gains.

I did some math, looked alright. But I'm worried about the unknowns, unexpected fees that MUST be taken by the users, and mostly taxes.

<comment><USER19> How could a cryptocurrency be backed by something?

If I need to "trust" you that I can get <something> in exchange for my cryptocurrency, then that's not much of a cryptocurrency is it? It may as well be a MySQL database controlled by you, as that's what it amounts to anyway.

<comment><USER20> I've been toying with the idea of a computation-backed currency. Any computer can obviously pay another computer in computer time. This means that any node in the system can issue currency backed by computer time. This would require trust, but it would be trust between neighbors rather than trust in one central exchange.

The problem is that that's not really a currency. It's zillions of IOUs. I don't know how to make transactions between two nodes that don't trust each other or how to come up with one number for someone's net worth.

<comment><USER15> Some economists would argue that "zillions of IOUs" is basically the precursor to currency/money. Then you just need a consistent unit, and that ability to trade/transact (which is a solved problem).

> Graeber proposes that money as a unit of account was invented the moment > when the unquantifiable obligation "I owe you one" transformed into the > quantifiable notion of "I owe you one unit of something". In this view, > money emerged first as credit and only later acquired the functions of a > medium of exchange and a store of value. [1]

[1] [https://en.wikipedia.org/wiki/History_of_money](https://en.wikipedia.org/wiki/History_of_money)

</comment></comment></comment></comment><comment><USER7> I'm very curious to understand this. Who is buying this? What is the real purpose? Who benefits in the end? Why is the daily volume 5 times market cap?

I wonder if it would be possible just through statistical or network analysis of all tether transactions on omni layer, without knowing the full narrative of Tether, to get some idea of the game.

<comment><USER21> Have not bought Tether, but the traders I chat with buy it before perceived dip then buy back into their tokens at bottom.

<comment><USER7> But why don't they buy regular USD? Ask them next time :-)

</comment></comment></comment><comment><USER22> I'm having a really hard time trying to understand how Tether can be used to buy Bitcoin if they are being made of thin air? Does anyone have a link to a good explination of how this works?

<comment><USER23> People are willing to trade other people by giving them bitcoins in exchange for tethers. Also, the same for US dollars and tethers.

</comment></comment><comment><USER24> This is the THIRD tether FUD article to make it to the front page today. What's the deal?

<comment><USER10> Billion dollar scams don't happen every day, they're usually worth talking about.</comment></comment>


SAT Data Tables - <AUTHOR> http://professionals.collegeboard.com/data-reports-research/sat/data-tables

<comment><AUTHOR> The submitted link includes sublinks to such details as the exact count of perfect scorers on the SAT in class of 2009 (184 males and 113 females)

[http://professionals.collegeboard.com/profdownload/sat_perce...](http://professionals.collegeboard.com/profdownload/sat_percentile_ranks_composite_cr_m_w.pdf)

and other details. The College Board 2009 College-Bound Seniors: Total Group Profile Report

[http://professionals.collegeboard.com/profdownload/cbs-2009-...](http://professionals.collegeboard.com/profdownload/cbs-2009-national- TOTAL-GROUP.pdf)

reports mean scores by student self-reported income category on page 4, table 11. The number of students with no response on family income is fairly high, and the mean scores of students in that category are similar to the mean scores of students in middle-class income categories.

</comment><comment><USER2> Any way to get this in a format other than PDF (so we can play with the data)?

<comment><USER3> You can use this: <http://linux.die.net/man/1/ps2ascii> to convert the text to txt...

or you can use something like this: <http://www.arizona- software.ch/graphclick/> to read the numbers off the plots.</comment></comment>


Ask HN: How often do you write custom SQL reports at your job? - <AUTHOR> At the last startup company I worked at as a backend dev, I was frequently asked to build SQL queries for the marketing, operations, and customer service teams. Typically, they would then dump the results into a spreadsheet and build charts or dashboards there.
I'm curious if you've experienced this as well, or does your startup just use a BI tool like Looker or Tableau for this?
I really enjoy writing SQL, but I'm not sure how marketable of a skill it is with all of the data analysis tools that are out there. Thanks! <comment><USER2> I've used SQL in every job/contract I've had in the last 10 years in different flavors. It's definitely a marketable skill.</comment>


Microsoft still doesn't "get" consumers  - <AUTHOR> http://owened.co.nz/the-problem-with-windows-tablets

<comment><USER2> I don't think Microsoft is completely to blame here, but I could be wrong.

One of the benefits Apple has is complete control over the hardware and software and the interfaces between the two.

Microsoft attempts to cover many more types of hardware where they don't have complete control of what devices their software is loaded onto.

It is the responsibility of hardware vendors to test their products and communicate with Microsoft about these issues.

Not to say this isn't a Microsoft problem. I think it is, in that consumers just want something that works, and I think Microsoft needs to be taking the initiative here and working closer with the manufacturers making sure the hardware works better.

I have no idea what their internal system is for this.</comment>


Show HN: Hacker Subscribe – Subscribe to your favorite users on Hacker News - <AUTHOR> https://www.hackersubscribe.com/ <comment><AUTHOR> I built a crude version of this for myself 18 months ago when I realized that Alan Kay occasionally posted on HN. I wanted to make sure not to miss anything he might say.

This is a beta version that anyone can use. Just select usernames and enter your email address, and you'll get notified whenever someone you subscribe to posts or comments.

      Tech Stack:
      Django/Python
      Vanilla JS
      autocomplete.js
      Postgres
      Heroku
      Redis Queues
      Postmark for emails
      Timber.io for logging</comment>


Ask HN: Would you use a cloud based browser session, browsethrough.me - <AUTHOR>

HNers,
I am a pack-tabber -- I typically have 20+ tabs open on a regular basis, on multiple machines for various purposes.
I have been sepc'ing the following service to address the issues I have with limited time, too much information, lack of organization. I am curious if you would use this service should I build it?
Browsethrough.me (or ill call it topicizer.com) is a cloud based browsing session which allows you to detach and reattach to various browsing sessions hosted via the service.
Group like site tabs together, such as a reddit session and the resulting cascade of tabs resulting from that session. An HN session or a work research session.
Lump sites/sessions together by topic as well such as "photography" "Ruby" "Programming" etc and be able to return to those sessions, share those sessions, tag them, add notes and potentially other actions.
Ultimately - what I would like to see is that rather than sharing a simple link, one could share out something akin to a digital tour; "Read this, then this, then look at this, and refer to this".
Considering the browser is such an important portal for everything we do, I find it odd that there is lack of deeper level features such as I have described to help people better manage access to online information.
If you find this interesting and would like to work on this with me, drop me a note. <comment><USER2> As someone who finds your "20+ tabs" cute (I've got an order of magnitude more per device), this is something I've always wanted. I did look into existing solutions, with Weave being the most attractive I found, but none really worked for me (the biggest problem with Weave was, unsurprisingly, browser dependency; I use multiple browsers on the same computer, let alone across devices).

It would be important to do this well. Speed and security are essential for this to be worthwhile. However, as far as the idea goes, I'm definitely game.

<comment><AUTHOR> I am not familiar with Weave -- I'll be honest, I did not look to see if anything was addressing this problem - I guess due to the fact that with as much as I read - I would have assumed to have heard about it...

What would you add/change with respect to the idea?

<comment><USER2> The idea with Weave was not exactly the same as yours, but it shares the same feature that I consider the main draw: sharing tabs across devices. Weave really is supposed to be a platform for sharing all of the browser data (history, bookmarks, etc) across devices, but the inherent Firefox dependency and cumbersomeness of use stopped me from using it.

Interestingly, at around the same time I was looking for that, I was also looking for a way to construct a digital tour such as you describe to use to show some things to remote coworkers, so I'm somewhat amused that you seem to be combining these ideas.

If you did end up creating a service that let me seamlessly share tab sessions across multiple devices on different platforms, I'd be ecstatic enough. Being able to tag tabs to various sessions and be able to pull them up like that so I could easily share the sessions for my projects between my work devices without bringing in, say, my HN tabs would just be a dream.

</comment></comment></comment><comment><USER3> I'm really not good with security & networking but how're you planning to prevent a Firesheep-like attack?

<comment><AUTHOR> Aside from the fact that this is not a solution aiming to fix wireless security, and other than offering the service via HTTPS - I am not sure that a "firesheep-like attack" is really a concern.

I suspect that the main argument against such a service would be the worry that your history / passwords / accounts what have you would be shared/sold/compromised.

I dont yet have the answers to such concerns, but I am interested in feedback on whether one would use the service assuming the stated security/privacy concerns were properly handled.

FWIW, I refuse to ever have a facebook account due to my complete lack of trust in that company's ability to act in a way I would be comfortable with as it pertains to any of my personal information...</comment></comment>


A Simple Visual Proof of a Powerful Idea in Graph Theory - <AUTHOR> http://nautil.us/blog/a-simple-visual-proof-of-a-powerful-idea-in-graph-theory <comment><USER2> Strictly speaking this "visual proof" is not a proof at all, it's just an illustration of one simple case. But what's good about is that it helps give you an intuition about why Ramsey's theorem is true: namely, that you'd eventually run into a dead-end when trying to color edges, in the sense that you're bound to create a sub-graph where all edges are either colored red or blue.

</comment><comment><USER3> I remember hearing about a social scientist "discovering" that in any classroom he visited, there always seemed to be 4 kids that were either all friends, or were all not friends. He wrote a paper that attempted to explain this using social theory/group dynamics...

(This was told by my Discrete math professor when learning about Ramsey's Theorem )

</comment><comment><USER4> The article says this is a useful tool, but doesn't say why. What's an example of something this is used for?

</comment><comment><USER5> "Ramsey's theorem states that in any graph where all points are connected by either red lines or blue lines, you're guaranteed to have a _large subset_ of the graph that is completely uniform—that is, either all red or all blue."

Can someone please explain how a large subset is defined? I am new to Graph Theory.

<comment><USER6> "Large subset" is not a technical term. The right question here is not "how is large subset" defined; it's "What does Ramsey's theorem actually state?"

A totally abstract version of the theorem would be (note: I'm only considering finite versions of Ramsey's theorem here), Ramsey's theorem states that given any n and m, there's a number R(n,m) such that if you have a complete graph on R(n,m) vertices, and you color each edge red or blue, there's either a uniformly red subset of n vertices or a uniformly blue subset of m vertices.

A more useful version would give an example of a number you could pick for R(n,m). (Normally we define R(n,m) to be the smallest such number, so you're giving an upper bound on it.) For instance, Erdos and Szekeres proved that R(n,m)<=(r+s-2 choose r-1).</comment></comment>


Ask HN: How to grow as an engineering leader with mid-level hands-on experience? - <AUTHOR> I worked in a startup from its inception until acquisition 7 years later. I started young as an engineer and did everything required to make the company successful - code, take support calls, conceptualize the product, go for sales pitches and meet with customers. I understood the levers of the company - employees, product, clients and was acknowledged as a good leader. When our team was growing I jumped to fill the gap of an engineering manager even though I didn't get the chance to grow via the typical engineering ladder of SDE 1-2-3 > TL > PE/EM. We had 20 engineers at our max size and my performance (getting things done, fostering team culture) was quite good. The CEO and the tech architect helped to take decisions on tech architecture whenever my skills were not sufficient. Together we built a great team and a profitable product.<p>I have an amazing experience building a company, but I am struggling to figure out what my next role is. Larger companies (50-200 sized company) don't think I am good enough for EM/Director of Engineering role as I haven't had extensive hands-on architectural experience. Is it normal for managers to have more breadth experience than depth? I understand I cant ramp up overnight. Assuming that I don't want to startup in the next few years, how do I grow from here? <comment><USER2> I would start with a basic question: what do you _want_ to do? Your current job let you explore a lot of topics and roles: which did you like best? Which do you see yourself pursuing for the next few years? Your post seems to imply that you're looking for management roles but it's unclear as whether it's because that's what you like to do or because that's what you feel you should do to grow your career. Word of advice: it's much easier to have a successful, fulfilling career doing what you love than eating shit every day doing something you don't like (management, architecture, product, whatever) but that you think is good for your career.

Once you've figured out what you want to specialize in (and make no mistake, in a larger company you'll have a narrower role than in a startup), write your resume around those skills. Market yourself (write a blog, try to speak at conferences, etc) as an expert in that topic. Identify what shortcomings you still have and work on them through side projects, reading books, taking an online course, etc. When you get to the interview stage and people point out your lack of expertise, explain (better yet, demonstrate through relevant examples) that working at a startup has taught you to pick up new skills quickly. Convince your future manager that it's in her benefit to recruit someone who knows how to learn new skills rather than a one-trick poney, even if the poney is very good at its one trick.

<comment><AUTHOR> The answer to "what do you want to do?" \- Long-term I want to start a company. Financial constraints and the current situation are not well suited to make decisions in that direction. Short term I want to continue to grow in management roles and acquire the skills needed to get closer to my long term plan. The approach you mentioned definitely helps. Thank you so much

</comment></comment><comment><USER3> I'm largely in the same boat. I was part of the founding team, architected our systems, wrote a good part of it, and eventually look over leadership of the engineering and product teams as the CEO had to focus on more external matters. I played the SE role on any meaningful call, worked closely with marketing, and even did sales directly a couple of times landing us an LOI at a critical time.

We had an "ok" exit, not enough to never work again by any means but it put some decent amount of money in the bank.

After riding out the acquisition for a year I've been looking for my next role and it feels like I don't fit in anyones box well enough to get the nod. Besides landing an exec position at a startup with funding, the big tech companies of the world seem like the only place to get good compensation for that expertise. From what I can tell, the big tech places don't seem to be interested in hiring people from startup-heavy backgrounds nearly as much as they used to be.

My approach is to try to reestablish some networks, and tossing resumes are interesting job listings. But the reality is that almost no one is getting hired for great roles without a warm intro to a hiring manager. Dusting off the old personal website never hurt either, it might at least let you get into the right kind of conversation after the warm intro.

It feels like I'd be in a great position to start a startup but with spouse and young kids its not the right time (especially now) to do that sort of thing.

<comment><AUTHOR> I can totally relate to your story. After reading your experience I am pretty sure there are many more like us. I played a key role in the growth of the company and was called a founding member on many occasions, but without a formal "co-founder" or CXO tag, it gets difficult to get an executive role in slightly larger companies. I guess starting a company is the most obvious option (assuming there are no other constraints)

<comment><USER3> From what I can tell even with the title it doesn't matter. I had CTO label and had our companies PMs reporting into me as well. Folks at bigger co's just don't seem to care and don't put value in the experience gained from "leadership" positions in startups.

From what I can tell you can still greatly increase your career velocity as an IC by doing a startup for a few years. It quickly falls away for management roles unless your company hits a big win AND you had a very publicly facing role, in which case the career boost isn't very needed due to the big win part.</comment></comment></comment>


Learning a hierarchy - <AUTHOR> https://blog.openai.com/learning-a-hierarchy/ <comment><USER2> It seems to me there's been an interesting turn in AI recently, toward focusing on adaptability as a goal in itself. Deep learning has shown that there is incredible power in stochastic gradient descent over a space of functions, but so far that has mostly been applied to rigid tasks. Now work like this is about turning that power towards adaptability itself as a goal, and it seems to me that this brings us towards "real" intelligence.

The logical extreme of this thinking would be agents that actually maximize entropy of future actions as the only objective function, like in [1]

[1] [http://paulispace.com/intelligence/2017/07/06/maxent.html](http://paulispace.com/intelligence/2017/07/06/maxent.html)

<comment><USER3> Is this like maximizing for movement options in a Chess AI?

<comment><USER4> This reminds me of a thought I had some years ago. The idea was that we can think of general intelligence not as an optimization for a specific given goal, but as optimization for a special position from which some wider set of goals can be most rapidly converged upon. Thus optimizing for future flexibility rather than current results.

At the time, I remember being excited to hear of a physics paper[1] concerning an inverted pendulum, where they solved the system for some dynamic forces which would keep the system at the position of maximum instability, and claimed that it was, in some sense, a description of dynamic intelligence. The analogy there is that this is the unique position from which the pendulum can be efficiently made to move quickly in any 'required' direction (the 'goal'.)

I still think that idea has some merit, but putting together a coherent formalization of it seems really tricky and requiring some genius far beyond my own meager pondering.

[1] I found the article: [https://physics.aps.org/articles/v6/46](https://physics.aps.org/articles/v6/46)

<comment><USER5> As a step in that direction, you can take some inspiration from what the brain does: as you learn things better and better, the knowledge essentially gets pulled down to neuronal layers that are closer to sensory input. This leaves the higher layers more free to do other stuff (potentially reusing the results from the surface layers), which is a step in the direction of optimizing for future flexibility.

It's possible to create rules that operate on an already-trained network and push it in this direction without totally destroying what it's learned, by "fuzzing" the original network to generate a bunch of input/output pairs, and then using that dataset to retrain smaller sub-networks. For instance, if you have a 5 layer network that you've trained on a classification task, you can often use that network as a teacher to train a smaller network to do pretty damn well on the same classification task, even in some cases where training the smaller network directly would have been very difficult. There are several reasons that this trick can work, not the least of which is that in a sense it is a way to expand the training set dramatically.

NB: the above approach is probably not how you'd implement this, there are less crude methods to incentivize shallower levels to have more activation than deeper ones that would probably work better

I can easily imagine a phased training strategy that oscillates between a) learning new things by making the deeper layers more malleable and the shallower ones fairly rigid, and b) compressing all the data by opening up the shallow layers to change and replaying input/output into itself. I have no idea if there are any benchmarks around this sort of thing, though, typically benchmarks have fixed goals so ability to retrain for additional tasks is not really measured.

</comment></comment></comment></comment><comment><USER6> super cool that this was done by a high schooler

<comment><USER7> More discouraging to me to be completely honest.

<comment><USER8> Why have a whole humanity if you only think a single best person has value?

<comment><USER6> "It is not enough that I should succeed - others should fail."

<comment><USER7> No it's not that...as tempting as that is often...

It's that the spoils of the new economy are accumulating in a way that completely forgets the middle 90% of the country. Kevin is obviously really smart, but has access to things I don't even have in a state school by virtue of being a sharp high schooler in Palo Alto, much less when I was in high school.

<comment><USER9> Life is long. If his location gives him access to opportunities that you don't have, figure out a way to get access to those opportunities and execute on it once you graduate from college. Many prominent Silicon Valley people came from small towns in the mid-west (Marc Andreessen, Evan Williams) or immigrated from poor political situations abroad (Sergey Brin, Jan Koum, Elon Musk).

<comment><USER10> very well said with annotated sample personalities who made it top of Silicon Vally ...

> Life is long. If his location gives him access to opportunities that you > don't have, figure out a way to get access to those opportunities and > execute on it once you graduate from college. Many prominent

> Silicon Valley people came from small towns in the mid-west (Marc > Andreessen, Evan Williams) or immigrated from poor political situations > abroad (Sergey Brin, Jan Koum, Elon Musk).

</comment></comment></comment></comment></comment></comment></comment><comment><USER11> Does this optimise the hierarchy as the environment changes? For example when cooking, I unpackage food as needed, but when it starts to clutter the workspace I make a decision to fit in a 'clean up cycle' while waiting on some other food to cook.

<comment><USER12> As far as I understood it, it learned sub-tasks then learned to apply those sub tasks.

Kind of reminds me of the Soar system except using Deep learning instead.

[https://en.wikipedia.org/wiki/Soar_(cognitive_architecture)](https://en.wikipedia.org/wiki/Soar_\(cognitive_architecture\))

</comment></comment><comment><USER13> I was mulling over this idea yesterday in the context of RTS games... There's no reason to consider changing your overall strategy every frame. Nice to see it works!

It will be interesting to see how it performs with more tiers in the hierarchy, and with more structured tasks.

Controlling a virtual arm to play a board game for example.

</comment><comment><USER12> Found the paper from the wired article below

[https://s3-us-west-2.amazonaws.com/openai- assets/MLSH/mlsh_p...](https://s3-us-west-2.amazonaws.com/openai- assets/MLSH/mlsh_paper.pdf)

<comment><USER14> There are buttons below the first video to read the paper and view the code.

</comment></comment><comment><USER15> Next step: transfer learning and sharing amongst sub-policies in the graph hierarchy. If an Ant Agent learns to "move up" to avoid obstacle or reach goal. Why can't it infer the same for any cardinal or diagonal direction, after observing the world around it. It's just a rotation or translation after all.

Also, for small numbers of sub-policies, would Monte Carlo playouts be faster. Where we are searching over the next step the Any may encounter. Which presumably is a finite set of possible "wall-floor" configurations ;)

In any case, great work! Always love watching OpenAI vids...

<comment><USER16> Well, it's really hard to read text upside down.

<comment><USER17> I've heard this many times, but I've never had any issues reading text at any angle.

</comment></comment></comment><comment><USER18> I don't understand where the 'hierarchy' comes into play? This reads to me as a standard computer program where you execute code, and some of those lines execute other segments of code which might be much more complex than what I see. If I execute the line 'printline('Hello World')' I only excuted one line, but many other things happened that I did not directly execute. I'm sure I'm missing something, and this is somehow different and novel, but I'm just missing it from this blog post.

<comment><USER13> It is effectively a system of reinforcement learning agents working in a command hierarchy to solve problems that single reinforcement learning agents fail to.

It's (somewhat)obvious that this is an idea worth trying. But that doesn't mean actually getting it to work is easy.

<comment><USER18> Got it, okay, so it is different from a traditional computer program, and more like a business or military unit, where the agent at a high level "determines" an action, and delegates the action to a lower level entity that doesn't necessarily have the knowledge as to why it's doing this thing?

</comment></comment></comment><comment><USER19> Is it just me or is there something revolting about the character model?

Good work nonetheless but for god's sake give it six legs and make it black

</comment><comment><USER20> Great work, Kevin!

<comment><USER21> :)</comment></comment>


Unladen Swallow is dead - <AUTHOR> http://groups.google.com/group/unladen-swallow/msg/bd4e6f935c23252a

<comment><USER2> No, it's not dead, and I'm sad that this is sitting at the front page, because it's so misleading.

The fact is, it's stalled ([https://www.google.com/buzz/bcannon/bZDN1jNZ3uC/Is-this- fina...](https://www.google.com/buzz/bcannon/bZDN1jNZ3uC/Is-this-finally- going-to-push-CPython-into-the)) - <http://www.python.org/dev/peps/pep-3146/> was accepted. This means that a branch was made with the intent of merging US into Py3k. Unfortunately, this proved to be a greater task then originally planned. Stalled != Dead.

To quote Collin: " _Unladen Swallow is stalled because merging the code into the py3k-jit branch plain sucks: lots of new compatibility work to be done, lots of corners we had to un-cut, lots of drudge and suffering. It doesn't help that Google is full of far more interesting and influential projects._ "

So add in the fact that the resources Google had "assigned" to the project got moved/reassigned onto something else, and what you have is a very stalled project. Collin has stated that they hope(d) that other python-core devs would/will step up to help, but everyone is pretty tapped out as it is.

I'm as disappointed as anyone that it's stalled - given it's compatibility with C extensions, potential speedups and future potential, it has been one of the projects I've had the most hope for.

That said, PyPy is also coming along; when they hit 2.7 compatibility and they have drop-in replacement capability, the ecosystem will be _very_ interesting. Competition in the interpreter space is _good_ , and I feel that Unladen's aggressiveness helped spur/move PyPy along.

That said Unladen (in my mind) remains the CPython interpreter's best way of moving into the future. It still has the most promise for _that_ code base.

<comment><AUTHOR> jnoller, I may have indulged in catchiness at the expense of accuracy and I am sorry if the title is misleading.

I hoped that this thread would raise some discussion about the status of US, as, after a lot of publicity on project launch, there have not been many official statements from the team. I have followed the project since the beginning and saw the exponential decay of traffic in the mailing list and commits as the promised performance improvements seemed less achievable (but it has to be said that the US team contributed to LLVM a lot of useful code, like gdb debugging of JITted code).

So my question is: why is US relevant since it hasn't achieved any significant performance boost? Why should we believe in the "potential speedups and future potential" if there is no evidence that supports them?

I myself had done some experiments with implementing a python JIT with LLVM some time before US was launched and had the same results, 10-15% improvement on microbenchmarks at expense of huge memory increase and compilation times.(see [https://groups.google.com/d/topic/unladen- swallow/bqf9TzWHht...](https://groups.google.com/d/topic/unladen- swallow/bqf9TzWHhts/discussion) )

It seems that the bottleneck is not in the interpreter loop, but in the CPython runtime API. I am afraid that, if the interpreter has to stick to CPython source compatibility, it cannot get rid of the overhead. But I would be very happy to be proven wrong.

<comment><USER2> When asked - on the mailing list, on google buzz, or anywhere else, Collin and Jeffery and others have been very open about its status. They've always dealt us (as the community) a fair hand about the status of the project, and the path moving forward.

Your indulgence in catchiness is annoying, as it will be echoed (and it already has been) all over the place with breathless drama "Look! It's Dead!" when, despite languishing, the code is still there, still functional, but starved of resources. The editorializing is frustrating, misleading and overall, I think harmful.

As for why it's still relevant: Easy, it's the only _currently visible_ way of moving the CPython interpreter forward from an evolution standpoint. US does show a series of speedups, one thats useful for CPython. To quote:

" _A JIT compiler is an extremely flexible tool, and we have by no means exhausted its full potential. Unladen Swallow maintains a list of yet-to-be- implemented performance optimizations [49] that the team has not yet had time to fully implement. Examples:_ " - <http://www.python.org/dev/peps/pep-3146/>

I would recommend: if you want to move anything forward, or help, rather than make posts like this, jump in on the <http://svn.python.org/view/python/branches/py3k-jit/>

Yes; part of the reason the current interpreter is limited _is_ due to backwards compatibility, but I'd rather have a limited JIT with some performance gains then none at all.

The fundamental issue is that Jeffery, Collin and Reid - the founding three are "off in the woods" - and they're the only ones who understand the code enough to move it forward right now. PyPy's success(es) are orthogonal to the evolution of the CPython interpreter code base.

<comment><AUTHOR> I am sorry this thread is turning into a flame... I would like to make clear that I am not questioning whether or not US is good thing to happen to CPython, just that it is now a project without maintainers (the post suggests that they will stop working on it after the py3k-jit merge) and without an active community. As you said it is a very complex piece of code and even if it is "still functional" it is definitely not ready, as the performance gains are not substantial.

I have nothing against calling it "stalled", but IMHO it is just an euphemism for "dead".

Also I don't understand why people at Google decided to stop investing on it, the cost of 3 full time engineers is nothing compared to the millions they would save with a more efficient python implementation, given their huge python infrastructures (App Engine, for example).

<comment><USER2> If this is a flame war, then it's a pretty tame one :)

As for Google's intentions, I've learned (as it has been explained to me time and time again) - never attribute smaller decisions to a larger strategy or "plan" of Google's. It probably not that they decided to stop investing in it, more than "something more interesting came up".

I do wish that we could have funded work on core/the interpreter. That would be nice.

</comment></comment></comment></comment></comment><comment><USER3> This sort of thing is one of the reasons why I'm very careful in picking the pieces that make up the tools that I earn my living with.

Left right and center you're bombarded with 'use this', 'use that', but most of these projects end up not having much staying power and if you depend on them for the running of your business then sooner or later you might end up having to support them.

When I choose an open source component these are the things I like to see in the eco system around it before deciding to jump in (obviously not every project selected will have all of these, but more helps):

\- multiple maintainers, active response to patches being sent in

\- broad support, using open standards

\- preferably a drop in replacement available

\- lively community of people willing to help each other out

\- two years track record with a good roadmap for future support

\- people working on it because they like it, not because they get paid to (this one is probably very counter intuitive when you're looking at this problem from a business point of view, but it is my opinion that people working on something because they like it are automatically in for the long haul).

Every time I've been seduced by new, hot and sexy technology I've come to regret it sooner or later. Old, boring and solid seems to win the race every time.

Running a small shop means that the investment you make in a tool is one of the most important decisions you can make, the wrong decision could cost you a lot of time and/or cripple your company.

I hope that everybody using unladen swallow is able to easily transition to a replacement.

<comment><USER4> There is no need to transition from unladen swallow since almost nobody was using it. It was a fork of cpython, and the speed improvements were so negligeable that I doubt anyone sane would try to use this without mastering the - heavy - technology behind.

I was actually quite shocked when unladen swallow was somehow almost accepted for python 3.2 at some point, given how bad the performance results were: if you add C++ + llvm and all the new infrastructure/complexity it brings, you rather have good numbers, not something like 10 % speed improvements which was the order of magnitude last time I checked.

It did bring useful code to python, though: in terms of benchmark code, but also proving that speeding up python while keeping cpython compatibility (vs just python compat) is actually pretty hard (which was expected, but they confirm the suspicion).

<comment><USER5> > I was actually quite shocked when unladen swallow was somehow almost > accepted for python 3.2 at some point, given how bad the performance results > were

Memory is getting cheaper. I was looking forward the GIL removal (at first), but I'll be happy with any multi-threading improvement.

OTOH, when I really needed it, the multiprocessing module did the job nicely. And it also prevents some very hard to catch bugs.

<comment><USER4> Unladen has never intended to remove the GIL - their primary goal was to keep compatibility with C extensions without even recompiling IIRC (google seems to rely a lot on python extension around their infrastructure), and removing the GIL will break many, many extensions: the only known way to remove the GIL without cause a huge slow down is to remove reference counting, which C extensions rely on, and also most C extensions rely on the fact they don't need to be reentrant.

<comment><USER6> Removing the GIL was one of the explicit goals as originally conceived, but was dropped when it was realized how difficult it would be (source: [http://code.google.com/p/unladen- swallow/wiki/ProjectPlan#Gl...](http://code.google.com/p/unladen- swallow/wiki/ProjectPlan#Global_Interpreter_Lock)).

</comment></comment></comment></comment></comment><comment><USER7> Reading the thread, it seems there's still an intention to roll the JIT into py3k at some point, but the project devs don't have the time and the community doesn't seem to have the inclination to take over the work. I think calling it dead might be overstating things slightly.

Or, seeing as this is Python we're talking about: It's not dead, it's just resting.

<comment><AUTHOR> The thing is, in two years the project was able to deliver only a very small, say 1.2x, speedup, with a noticeable increase of memory (sometimes 3x). Against Python 2.6. I wouldn't be surprised if Python 2.7 is actually faster on some tests. Is it really worth keeping working on it and merging?

<comment><USER2> Part of the reason Python 2.7 is _faster_ on some benchmarks is because of the patches the unladen swallow team pushed upstream into core.

</comment></comment></comment><comment><USER8> With PyPy moving ahead so well, I wonder if there's much point to Unladen Swallow anymore. Weren't they always expecting to be a stopgap until PyPy was ready?

<comment><USER5> Last time I checked, PyPy wasn't compatible with modules written in C. That's a show stopper for many of us.

<comment><USER9> _Can I use CPython extension modules?

Yes, but the feature is in alpha state and is available only on trunk (not in the 1.2 release). However, we'll only ever support well-behaving CPython extensions. Please consult PyPy developers on IRC or mailing list for explanations if your favorite module works and how you can help to make it happen in case it does not. We fully support ctypes-based extensions, however._

[http://codespeak.net/pypy/dist/pypy/doc/faq.html#can-i- use-c...](http://codespeak.net/pypy/dist/pypy/doc/faq.html#can-i-use-cpython- extension-modules)

<comment><USER5> Wow! That's really cool!

<comment><USER10> Their working on it...

</comment></comment></comment></comment></comment><comment><USER11> Unladen Swallow looked very promising, came out with lots of excitement and news. It overannounced and underdelivered. I tend to prefer underannouncing and overdelivering...

<comment><USER5> If you never fail, you need harder things to do.

<comment><USER12> On the other hand, if you never _publicly_ fail you may just be prudent. Or paranoid. Or depriving yourself of some beneficial pressure. But it's not quite as clear-cut as you make it seem.

</comment></comment></comment><comment><USER13> Nice editorializing there. I suggest readers who care should read the entire thread, and be careful when they see future posts from "ot".

<comment><USER14> I read the entire thread and it seems to me that the project is dead (or not very far from it).

      Jeffrey and I have been pulled on to other projects of
      higher importance to Google. Unfortunately, no-one from
      the Python open-source community has been interested in
      picking up the merger work, and since none of the original
      team is still full-time on the project, it's moving very
      slowly. Finishing up the merger into the py3k-jit branch is
      a high priority for me this quarter, but what happens then
      is an open question."

When working on open source, especially something as complicated as this, you need at least one dedicated maintainer. Looks to me that they are trying to do the responsible thing and tie up any loose ends.

</comment></comment><comment><USER15> Are we reading the same page? I don't see anything saying it's dead. Perhaps out of focus, but there's still a plan to merge.

<comment><USER16> I don't either. This same thread gets posted on Reddit's /r/Python seemingly once every few weeks and everyone freaks out all over again.

</comment></comment><comment><USER17> It's not dead, it's just pining for the fjords.

</comment><comment><USER18> Is there a wise one among us who could summarize the characteristics and status of the various Python interpreters us Python amateurs should be excited about?

<comment><USER19> Here is a comprehensive list of Python implementations: <http://wiki.python.org/moin/PythonImplementations>

</comment></comment><comment><USER20> Funny, I was just talking about them not being able to remove the GIL today while working through a tornado app.

I wonder what the future holds for pypy.

</comment><comment><USER19> It's not dead, it's sleeping.</comment>


Formula 1: Building the world's fastest cars - <AUTHOR> https://arstechnica.com/cars/2017/04/formula-1-technology/ <comment><USER2> I'm a diehard racing fan and F1 is the absolute pinnacle of car technology. I go to the Montreal Grand Prix every year (Singapore this year) and it's by far the most exciting point of my year.

The only thing though... with this insane technology, we see less and less 'real racing' which is a shame.

I read an article (will try to find it) that was saying last week at this year's first race, there was only 1 racing pass the whole race.

It's become a challenge of who has the best first 3 seconds of the race to get into pole position. Once you are in first, besides a strategical error by your team, you can essentially stay in first for the rest of the race.

I'm a Ferrari fan and am hoping this year they can shape up, but I want to see some more passes!

My dad is a Formula 1600 driver here in Canada, and the 1600 races are ridiculously exciting. Open wheel madness, passes all over the track, so much fun.

<comment><USER3> F1 is totally _not_ the absolute pinnacle of car technology. It's the premier _racing series_ but the hypercar projects such as the Red Bull / Aston Martin and the AMG project will shame any F1 car because they don't have to conform to a rule book.

Sorry, there's just no way putting a bunch of limits on stuff like traction control and other "cheats" counts as being the absolute peak when there are road-going examples of cars with superior tech from an objective standpoint.

<comment><USER4> Nothing can beat how motorsport looked backed in the '80s - early '90s. There was the B Group rally class, which has since grown into a myth among racing enthusiasts, there were the really interesting Le Mans prototypes of the late '80s - early '90s (the Mazda 787B is still considered by many as the car having the best engine sound ever), the Dakar race was still an adventure in itself with really intense competition and wonderful cars.

And there was also the greatest pilot that I've ever seen driving (I'm 36 now), Ayrton Senna. [https://www.youtube.com/watch?v=7BoukLE8V7M](https://www.youtube.com/watch?v=7BoukLE8V7M) , you can see that back then drivers had to take their hand off the wheel while negotiation a curb at 280+ kph in order to change gears (and he was adjusting his visor at 300 kph). And the sound, the sound is irreplaceable.

Later edit: I forgot to mention DTM. Found this YT video 2-3 months ago ([https://www.youtube.com/watch?v=Gw- AxiVqihM&](https://www.youtube.com/watch?v=Gw-AxiVqihM&)) which I now listen/re-watch every week or so. Almost all the cars in that video are now car enthusiast classics. If I ever were to become a millionaire I'd buy a 190E 2.5-16 EVO2 in a second.

<comment><USER3> Don't forget the Chapparal cars! The first with active aero (a movable spoiler/wing), and then also with the famous "sucker car" that had a vacuum assist for traction.

I'm really with you though that racing series and "progress" also has a big incentive to increase safety and reliability and blah blah blah. I do very much love the quote from "Rush" (super well flimed I must say) about how being on the edge of death "is a wonderful way to live" because of how alive it makes us feel. I know that hasn't changed in motorsport, but simply evolved. Nostalgia certainly has its place.

</comment></comment></comment></comment><comment><USER5> I wish the actual Formula 1 race shows would make more use of explanations and technical details. There's some mentions during the race by the reporters of some aspects of the technology, but they could do a lot better before and after with animations etc.

I watched this Top Gear video a while ago, showing one of their guys trying to drive a F1 car (and one of a slower league) around a race track, which is pretty tough if you're not trained to do so, because of the massive G-force in the turns. [https://www.youtube.com/watch?v=9773pisjCSw](https://www.youtube.com/watch?v=9773pisjCSw)

Compared to that, the race reporting often looks kind of dull and slow.

<comment> k-mcgrady What country are yo watching F1 in? In the U.K. I find there's a fair bit of technical content (obviously they can't do too much as a lot of people won't care).

<comment><USER6> For context, which channel?

I watch Sky F1, which provides a decent amount of technical context, but I don't know what content is delivered by Channel 4, or how it compares to Sky.

<comment><USER7> Channel 4 coverage is brilliant, especially the technical side which is covered by Karun Chandhok. I actually watched the Sky stream live last weekend, and then tonight I watched the Channel 4 highlights as well purely for the coverage around the race.

Having watched at least a few races from every season since 1979 onwards, I'd say Channel 4 is the best reporting team Formula 1 has had so far.

</comment></comment></comment></comment><comment><USER8> I grew up around racing and cars, not F1, but SCCA, NHRA, NSCAR and the like.

F1 is just plain boring. Yes, the tech is ASTOUNDING and really got me into engineering to begin with. Taking into account the elasticity of titanium piston rods, the down force aerodynamics, the regen braking, all that jazz, it is all SO COOL.

But, as other commenters point out, the race is won in 10 seconds, there is no passing anymore. Like the recent Pacquiao or Rousey fights, you can't even enjoy a single beer before the event is done. There is no drama, there is no excitement, just a ton of talking by boring people trying to fill time. In F1, it becomes a match of who does not screw up and make a mistake.

Why watch that? How can I get my own kids into that kind of a 'sport', to them is it their father sitting on the edge of the seat for about a minute, then hours of nothing. _Why would they want to watch it?_ They know that they will never be able to compete at that level, as they know it is all about the money that we don't have as a family. No amount of hard work will get a little boy into those seats if dad is not a _B_ illionaire. _Maybe_ they can study really hard and become a person that does CAD models for one of those teams. But there are no dreams of F1 cars for little boys anymore. So why bother? What does F1 have that could keep me watching? If you believe the stats, a lot of people are asking the same thing: [http://www.f1fanatic.co.uk/2016/04/20/f1-has-lost-one- third-...](http://www.f1fanatic.co.uk/2016/04/20/f1-has-lost-one-third-of-its- tv-audience-since-2008/)

<comment> k-mcgrady You say all that like it's fact. Personally I love F1 for the strategy. Watching a car slowly close on another car 0.25s a lap for 20 laps is thrilling. Trying to figure out where people are coming out after pit stops and whether they're lap times are good enough is fun.

I feel like the argument that 'there is no overtaking in F1 so it's bad' is akin to people not liking Soccer because there are never more than a few goals a game. There's much more to it than that and their are other series that cater to people who just want lots of passing.

<comment><USER8> Yes but in soccer, both teams start with 0 points and can tie. You can't do that in racing (a tie does happen but is so rare, it might as well never happen). Would you like to just watch cars draft each other for 3 hours and never actually overtake or _try_ to win? Because that's what F1 is kinda is, a 15 second death scramble at the front of the poll followed by a non- competitive Sunday drive at extreme speeds. The damn time trials for poll in NASCAR are more worth watching, at least they are trying to go fast.

<comment> k-mcgrady No overtaking != no competition. The competition largely comes down to strategy now. I find nothing more boring than racing series where cars are constantly overtaking each other. It just gets boring and repetitive.

<comment><USER8> Wait, define overtaking. I would define it as: My team moved into 15 place, from 16th, thereby increasing my chances of winning the race and the season title. Are you saying that overtaking can _or_ cannot occur due to pit stops and the like? Because if I am reading you the way I think I am, you are saying that there can be competition even though no-one changes place in the race. If you are saying that, we just have fundamentally different ways of defining entertainment/fun. For me, overtaking and changes in position with the goal of taking 1st place are _the point_ of racing no matter the venue (foot-races, boats, etc). For me, if you aren't trying to take 1st, you might as well hold the competition in your backyard.

</comment></comment></comment></comment></comment><comment><USER9> Here's one lap onboard from last weekend's qualifying, showing 6G+ forces many times over the course of a single lap: [https://www.formula1.com/en/latest/features/2017/3/f1-video-...](https://www.formula1.com/en/latest/features/2017/3/f1-video-2017-vs-2016-g-force- comparison.html)

And that track isn't even one of the most demanding ones.

</comment><comment><USER10> For me, endurance racing (WEC) is quite a bit more fascinating and impressive than F1. Racing a car on the cutting edge of race technology for 2 hours is one thing, but 24 hours is a whole different ballgame.

<comment><USER11> The other thing that WEC has that Formula 1 doesn't is the chaos and excitement caused by multiple classes of car competing at the same time. It's not just a matter of negotiating your car around all the other cars that are pretty much identical to yours. You have to negotiate around cars that are both slower and faster. Dealing with traffic is a major aspect of WEC, and it's something that's entirely lacking from F1.

<comment><USER12> If you like the chaos and excitement of WEC you should come on over to WRC. $5/month for 3-hours of live streaming HD content per Rally, including full on-board cams for every major driver and stage:

[https://plus.wrc.com/](https://plus.wrc.com/)

I mean c'mon, Kris Meeke with an accidental exit into a car park with just a few corners to go while leading Rally Mexico. You can't get much more exciting than that!

[https://www.youtube.com/watch?v=ECS_GXIJ200](https://www.youtube.com/watch?v=ECS_GXIJ200)

<comment><USER11> I already have :) WRC is fantastic.

At this point, I think I'm supposed to whine about how "modern rallying doesn't hold a shadow to Group B" :)

</comment></comment></comment></comment><comment><USER13> If you really want to geek out about F1 (which is incredibly fascinating from a rules and sheer technical wizardry perspective), I would highly recommend the F1 Technical forum.

[https://www.f1technical.net/forum/](https://www.f1technical.net/forum/)

<comment><USER14> Though, now dated, I'd also recommend [Steve Matchett's books]([http://stevematchett.com/](http://stevematchett.com/)). Previous mechanic, and now commentator (which, yeah, some people hate... but i love the guy). Interesting insider perspective.

<comment><USER15> I don't mind most of his commentary, except for the bit where he calls all the teams by their home city. People don't really care about Brackley vs. Maranello.

<comment><USER7> I've never seen Steve's commentary (although I do love his books), but those references could be useful in appreciating the lineage of the teams on track, e.g. the consideration the the team that once was Spyker finished 4th in the championship last year.

<comment><USER15> Yeah, I don't mind it occasionally, but he'll open up qualifying with something like, "Well today we're going to see if Maranello can take the fight to Brackley," and I wish he'd just use the team names.

On the other hand, I really look forward to hearing Hobbs go "Whoeuueeuuueeeoaa!!" midsentence every time someone gets even slightly sideways.

</comment></comment></comment></comment></comment><comment><USER16> So much emphasis on Microsoft technology in here. Veiled advertisement?

<comment><USER17> I thought the same thing while reading the article. The whole part about Power BI is definitely an advertisement, it has little to do with the rest of the story.

</comment></comment><comment><USER18> 25 teraflops and not a drop more - I did not expect to see a limit for the hardware used for simulations!

</comment><comment><USER19> Richard Hammond's Engineering Connections on F1 [1] is a great watch for some of the technical details.

It is however a bit dated; there have been changes to the rules and the cars themselves since the video was made. The Reddit guide [2] to F1 is more up to date.

[1] [https://www.youtube.com/watch?v=QC_gpr2xAjk](https://www.youtube.com/watch?v=QC_gpr2xAjk)

[2] [https://www.reddit.com/r/formula1/wiki/newtof1](https://www.reddit.com/r/formula1/wiki/newtof1)

</comment><comment><USER20> So both my wife and I watch every race. I have been to the Singapore race in the past. What an amazing party. The races themselves are getting to be quite dull. The lack of passing and things like DRS have made the racing all about the first few seconds. With the exception of Max V. amazing driving in some of the races last year it is not as fun as it used to be. I really wish they would mandate a single engine and a singe car type. Lets make it about the drivers and the strategy. The teams with the money win here.

<comment><USER9> But you're missing the point. This sport is about engineering teams competing to build the best machinery. It's probably the best manifestation of technology applied as a sport.

<comment><USER21> Then why don't we just forgo human drivers, if it's only about the engineering teams. Just have self driving cars battling it out.

In my opinion, F1 should go back to manual transmission, and no driver assists. Do whatever else you want to make the car perfect, but the driver must be in control of the entire machine.

Just look at the 80's in those monstrous turbo V6's approaching 1500HP, no traction control, no power steering, and manual transmission. THAT was driving.

<comment><USER9> It's not only about engineering teams... but about teams (engineering + driver). Obviously the human drivers, and the drama they generate, is what makes the race worth watching. But giving the driver a good car is a fundamental part of the game.

<comment><USER21> Thus my response.

</comment></comment></comment></comment></comment><comment><USER22> I hope self driving cars take the crown in the future. The more the F1 is regulated the more boring it get's (at least for me).

Since no driver is in danger they could make the cars faster and the race tracks more interesting. Maybe this will revive some of the race tracks that apparently are not on the F1 list anymore because they are to dangerous.

Or in the far future even high speed racing with weapons like in the games Rollcage, Wipeout, F-Zero and Extreme-G (of course with technology that is available...)

<comment> k-mcgrady Self-driving car races sound like the most boring thing imaginable to me. Drivers don't have to be risking death (and they are, and they have died recently) to make the sport exciting. They have to be in immensely good physical condition to drive those cars and they have to have better race craft than ever as overtaking has become more difficult too. I'm not saying self- driving cars couldn't be it's own series but it would never reach the level of F1/WEC/WRC in terms of popularity. Nobody wants to cheer on a CPU.

<comment><USER23> I have started a competition for autonomous vehicles. I struggle to see much spectator interest as well. I see it has more of an engineering competition that happens to culminate in a race.

That said, most of amateur racing has no spectatorship either.

[http://selfracingcars.com](http://selfracingcars.com)

</comment></comment></comment><comment><USER24> Funny title. FIA has, for decades, been explicitly forcing the cars to not be the fastest racing cars with byzantine restrictions on the design of the cars and even _how_ they can be designed. I gradually stopped watching F1 races through the late 90's because there was less and less racing and the winning cars were more and more determined by how the engineers found loopholes in the rules for one season until those got regulated or banned for the next season.

If they just gave everyone the same car and let the teams augment the base construction instead of building a new car from scratch then the drivers' skills would be more emphasised and leave more room for race action. Also, the more activity there is during the race the more entertaining.

<comment><USER25> I have the opposite impression: it seems to me that FIA regulations are making the cars pretty much the same for all teams.

<comment><USER26> That is the main goal, but take the turbo switch in 2014 as a counter example- Mercedes out their turbo-charger inline with the engine, and no other teams did this[0], so they dominated for years. So yes, if you have the most money for engineers and parts, you generally have the best chance of winning.

[0]:[https://www.wired.com/2014/04/mercedes-f1-turbo/](https://www.wired.com/2014/04/mercedes-f1-turbo/)

</comment></comment></comment><comment><USER27> I think PG once wrote an essay explaining that most press is agenda-driven and there's somebody with money behind the story.

I wonder if that's the case here. F1 just passed out of Bernie Ecclestone's hands and has a new leadership team as well as shareholder base. They are aiming to revamp the sport and make it more exciting by addressing a lot of the issues brought up in other comments, like the rules stacking the deck in favor of rich teams and the fact that there is no streaming/digital option available to global fans.

</comment><comment><USER28> If I ruled the world, F1 cars would not be allowed to use any electronics other than in safety systems. Something about a computer taking the place of clever mechanics sucks the joy out of it.

<comment><USER29> And no aerodynamics active or otherwise. :-)

<comment><USER28> Yes.

Tuning up a race car with a laptop just seems like cheating to me, they should be tuned by ear :-)

</comment></comment></comment><comment><USER30> Clickbait title. (technical deep dive? really?).

<comment><USER31> OK, we've taken that out of the title since interpretations may vary and the article is represented just fine without it.

<comment><USER32> The irony is there's still a rather obvious factual error left in the title, in that the slowest top fuel dragsters are well over 100 MPH faster than the fastest straightaway speeds of F1 cars.

Eventually the title is going to be chopped down to not much more than "F1" LOL.

Due to continuous modification of the rules, today F1 cars are faster than NASCAR but its an incredibly close race (LOL the pun) and it seems inevitable that given the constant turmoil of the rules there will eventually be a season where the top NASCAR speed is higher than the top F1 speed for that season.

So if its not bad enough that the dragsters are faster than F1, its only via extensive rules manipulation that the fastest NASCAR cars are not occasionally faster than the fastest F1.

<comment><USER33> The absolute fastest "cars" in the world tend to be the jet-propelled vehicles solely built to break land speed records (I believe the current holder is this car: [https://en.wikipedia.org/wiki/ThrustSSC](https://en.wikipedia.org/wiki/ThrustSSC))

A jet car isn't going to be able to be driven very easily on a closed race course, though. :)

Many cars are designed to be fast in one way, but not as quick in other ways. Cars designed just to go straight (like dragsters) do not need loads of speed- robbing downforce for taking corners quickly.

Formula 1 doesn't even hold the fastest lap ever recorded by a sanctioned racing series... as far as I know, that would be CART / Indycar, who achieved a 241mph (387kph) qualifying lap at Fontana ([http://www.prnmag.com/columns/44-columns/66-who-holds-the- wo...](http://www.prnmag.com/columns/44-columns/66-who-holds-the-worlds- closed-course-record-aj-foyt.html)).

But Formula 1 doesn't run on banked ovals like Indycar does.

Circuit Gilles Villeneuve has hosted a lot of series, including both Formula 1 and the NASCAR Nationwide series. There's a comparison of record lap times at the end of the Wiki article ([https://en.wikipedia.org/wiki/Circuit_Gilles_Villeneuve](https://en.wikipedia.org/wiki/Circuit_Gilles_Villeneuve)). At least here, it seems that Formula 1 is a fair bit quicker than Indycar and loads quicker than the saloon / sport type cars. For this particular type of course, they probably _are_ the fastest racing class.

<comment><USER34> F1 is about 10x better than other racing series or car tech. The top speed and power obviously not. But look at the max. rpm. Capped now at about 20k, but they can easily go to 26k. F1 is all about high freq and acceleration. Internal systems are running at 10khz cycles, normally a NASCAR or normal car Max is 500-1k. F1 dynos are small monsters compared to NASCAR. Dragsters have strong power, 3x more than F1 with stronger dynos but this is like a ship dyno. You could use cheap hydraulic dynos to test them.

Transmitted data rates and sensors are insane, team budgets ditto. NASCAR and Indy could never use that much sensor tech as F1. They are highly motivated, but it's a different league. The F1 dyno tech would blow away any Tesla e-motor.

<comment><USER35> No, 20k rpm was "the good old days". Now they are limited to 15k.[1]

I think the engine manufacturers were the ones pushing for all these rule changes. The reason is the manufacturers want to be able to utilize this technology in their road cars. Just look at turbos, not too long ago F1 went turbo (again). Not coincidentally many recent road cars are turbo. E.g. Honda has turbos in their econoboxes.

[1] [https://www.formula1.com/en/championship/inside-f1/rules- reg...](https://www.formula1.com/en/championship/inside-f1/rules- regs/Power_Unit_and_ERS.html)</comment></comment></comment></comment></comment></comment>


Ask HN:  When to release?  - <AUTHOR>

I've been toiling with this question this morning and curious to hear the thoughts of HN.  This isn't a purely academic exercise as I'm planning on launching a startup in the next couple months and this is an issue I have to grapple with. Rather than speaking in generalities I'll layout an example.  Say you are Pandora and you are building the first music recommendation engine or you are Farecast and building the first prediction model for airline tickets. These companies spent years developing their predictive technologies and they are assuredly extremely comprehensive and robust.  However, say they gave themselves a 2 month deadline and released a service which they strove to improve over time.  Their service was not nearly as prescient as it could be if they took 3-4 years to develop it. Still, there was some data analysis that went into the service and Pandora and Farecast could advertise that fact on the website and indicate that the results will get better over time.
How many users would these services have lost?  Some users will be dissatisfied with the services so they would lose potential customers. Also, another competitor could see that they could do better and launch their own service, diluting the market share for these comapnies. But these companies sacrificed revenue by not releasing their service until it was very strong. Also, there are other companies that took years of work and flopped miserably upon release. Farecast and Pandora faced the risk of joining that unenviable pool.
It's hard to argue that Farecast and Pandora went down the wrong path since they were super-successful startups. But if I'm not mistaken, both started in academia so they have a higher standard to live up to in terms of rigor. Most startups are under the pressure to launch something quickly.  If you were running a similar company, when would you launch? <comment><USER2> I think you should launch as soon as your service provides enough value to someone that they should care. If no one cares, it doesn't provide enough value (for whatever reason). If people do care, then you know your on to something.

If you launch before you provide enough value, no one will care.

If you wait to launch, you are only doing yourself a disservice by delaying or prolonging the feedback cycle. You should be doing the opposite, figuring out how to make your feedback cycle as short as possible.

Worrying about competitors at this stage is dumb. You could only be so lucky as to have an idea good enough that someone would care enough to try to challenge you for it.

<comment><USER3> _I think you should launch as soon as your service provides enough value to someone that they should care._

Yes. In general, you should release at the point when there is at least some set of users, however small, whose lives will be improved enough by whatever you've built that they'll start using it.

</comment></comment><comment><USER4> One of the advantages you have as a start-up vs. larger corporations is that you CAN launch something before it's "ready". Getting feedback quickly and early is essential to evolving your product.

It's common knowledge that the earlier a bug is found the cheaper it is to fix. Same goes for problems in UI design, etc.

</comment><comment><USER5> One thing to consider is to what extent the user will be depending upon the quality and comprehensiveness of your specific product. A product used for recreation or convenience may be very partial and/or may fail frequently without causing much disappointment, and users may be happy to have it early. In contrast, my startup made a product that many users considered vital to their professional and business success, that required substantial initial investment of effort, and that users often used under considerable time pressure. Anyone starting to use the product who became wedged by incomplete features would be extremely unhappy. For this product, it was necessary to get it over a fairly high threshold before offering it (apart from a demo or alpha with no expectation that it could be depended upon). Most products aren't in this category, and profit from early release. But even so, for your specific example, I tried Pandora on its release day and was disappointed, and wrote to Tim Westergren to tell him so; he answered within minutes promising future improvements, which should have been impressive enough, but it took me two or three years before I tried Pandora again (I'm now an enthusiastic paying subscriber).

</comment><comment><USER6> That depends on what you're trying to build. For most startups, getting early users (not a full launch but a limited alpha/beta) is key in developing a good product.

Sure, given more time you could just keep perfecting the product to your standards, but if you don't have a good idea of EXACTLY what you're building, why not do a limited release and work with the feedback that these alpha users give you to improve your product as opposed to waiting for a really long while before you release something that you (not the market) thinks is perfect in every respect, that sounds like a really good way of failing.

Yes, you're going to lose some people who will hate the product and find it useless, maybe they're not your target market. Maybe they are, if they are, listen to the feedback that they give you and hopefully retain them. If not, well, you don't care about them anyway.

3-4 year long dev cycles are generally not a good idea, since user driven development is key in making good products.

You can do it if you're Apple and you have the in-house expertise and market research to know EXACTLY what your users want, but if you're a scrappy startup, you have nothing to lose by launching early, and often and failing fast.

<comment><USER7> Indeed. 25 people who'll give you a page of detailed feedback once a week could save you months of frustration and wrong turns. If your site depends on a networking effect of some kind, you might be able to recruit Alpha testers who'll agree to roleplay all being interested in the same topic.

</comment></comment><comment><USER8> There's no rule of thumb when it comes to launching. Everyone recites the rhetoric of release early and iterate often, but that can lead to releasing a premature product.

Your product only has one reputation, so more important than "when" is "how". You'll want to make sure you have at least a differentiating feature, a marketing plan in place, and a good initial spike of users to even begin to draw worthwhile feedback. Having small sample sizes just leads to noise, which can then lead to even more indecision than you began with.

The best way to think of a launch is not as a switch you flip, but as a reveal that you build up to. The balsamiq guy had a great blog post about prepping for launch: [http://www.balsamiq.com/blog/2008/04/18/preparing-for- launch...](http://www.balsamiq.com/blog/2008/04/18/preparing-for-launch/)

It's as close to a video game walkthrough as you'll find.

<comment><USER4> Here's how I prepare for a launch:

1) log on to server 2) svn up 3) go to apache directory 4) bin/restart

<comment><USER9> Same for me, except change step 2 to "git pull" and 5) sound the alarm

</comment></comment></comment><comment><USER10> Is your product good enough to blog/tweet/tell friends about? If so, you're probably ready to launch. If you think it'd get bad reviews, keep working.

</comment><comment><USER11> Depends on whether what you're building is free or costs money. Each results in different expectations on what you provide at launch.

</comment><comment><USER12> Common creed I've read around the startup world seems to be "release early, upgrade often", but I've always thought you must have a strong (note: strong doesn't mean many) set of features before launch.

</comment><comment><USER13> I think it depends a lot on what your service is. I'm working on a startup for hikers (trailbehind.com) and we were live from day one. But most of our traffic comes from searches, and we've gotten more and more traffic from searches as we've gotten better and more popular. We've also had some hard core outdoors fans find us and send us great suggestions and even data. But if we were a service like Pandora, that model wouldn't have worked, since people would have had to remember to come back after a bad experience.

</comment><comment><USER14> One important factor to consider is scalability. A lot of people like to launch with a relatively immature server that only supports a relatively small # of people in a beta with the idea that they will expand it after that # of people come in. I think this adds an extra risk of someone absorbing your ideas and it's better to get a nice, horizontally scalable server. You don't want to break on slashdot or techcrunch and then have the site go down under load.

</comment><comment><USER15> I am always for launching as soon as your thing is operational. Real users and critics need to shape your startup and technology, and nothing can replace that.

</comment><comment><USER16> I like the minimum viable product approach:

<http://venturehacks.com/articles/minimum-viable-product></comment>


Defining Transit Service Areas with Unsupervised Machine Learning - <AUTHOR> https://towardsdatascience.com/how-does-the-bay-area-commute-22f45e00419e <comment><USER3> Interesting application of clustering.

My group in the UK (Amey Strategic Consulting: [https://www.amey.co.uk/amey- consulting/services/strategic-co...](https://www.amey.co.uk/amey- consulting/services/strategic-consulting/) ) have been doing very similar things for a while now to optimise utilities maintenance, for example optimizing the number and position of maintenance depots to enable a utilities company to undertake repairs most efficiently.

I'm UK based, and not that familiar with the Bay Area - but I guess there are a whole bunch of follow-up questions. Most pertinently - what would this change. Suppose (for example) you created a North Bay Transit Authority - <USER2> would a common ticketing policy affect commuting patterns. Is the issue the cost and inconvenience of multiple tickets, or the disjoint nature of current services?

<comment><USER4> Are you aware of the classic four-stage traffic assignment model? It's the linear regression of transportation modeling. It's scary that the authors didn't even mention that it exists.

[https://en.wikipedia.org/wiki/Transportation_forecasting#Fou...](https://en.wikipedia.org/wiki/Transportation_forecasting#Four- step_models)

My first job was to estimate trip generation models (the first tier) using simultaneous-equations time-series models in Eviews; a transportation engineer with some experience doing surveys (i.e. coordinating teams of people with clipboards) worked on the mode choice. We had additionally some greyheads who had the Matlab codes for trip distribution and route assignment.

Realistically some machine learning type classification could really help in mode choice, particularly if raw data (like turnstile pushes) is available. Trip generation, like most microeconometrics with time-series, is something of a dark art.

Ideally we would all be doing agent-based simulation by now with super- disaggregate data like Waze has, but I haven't seen complex systems simulation really "arrive" for real problems. It'd be fun to train reinforcement learners on them too :)

</comment></comment><comment><USER5> In germany, there are a lot of the "Verkehrsverbünde" and they work very well. For example, in munich there's the MVV (Münchner Verkehrsverbund), but the s-Bahn (slimiliar to BART) is operated by the Deutsche Bahn and the underground, tram and busses are operated by the MVG (the communal transit company). There are, of course, problems in most of the public-transportation networks in germany, but I don't think they are to blame. I think it's a pattern worth copying.

It even allows for some competition because you separate the provider from the system. For example, in nuremberg the provider for the s-bahn for next few years was recently auctioned off to another company after frustration with the deutsche bahn.

</comment><comment><USER6> This is cool. I'm working on something similar to divide up areas for municipal waste collection based on travel times between properties.

> for this problem, we are defining the distance matrix directly from the > source data. This results in the unusual property that the feature space > distance from A to B is likely to be different from the feature space > distance from B to A, as more commuters will commute in one direction than > the other. For this project, we made the decision to examine origin to > destination commute flows only, as this resulted in the clusters that were > clearly defined in both feature space and real space, while the inverse > resulted in clusters that were significantly overlapping in real space.

I had a similar problem, since the travel time from A to B can differ dramatically to that from B to A. I experimented with a few different ways of symmetrising the matrix and found that taking the maximum of both values was a pretty good compromise.

I also found that hierarchical clustering didn't work as well as K-means/medoids when the "clusters" were not necessarily very well-defined and the number of data-points was in the thousands.

<comment><USER3> @n4r9. Where in the world are you working? I would be interested in getting in touch. You can reach me at stephen dot gooberman hyphen hill at amey dot co dot uk

</comment></comment><comment><USER7> This article was very underwhelming. It's viz porn dressed up as something insightful. Looking at his clusters, he managed to "find" the transit systems. That's not particularly interesting. It's even less interesting because at the start he talks about how you can't combine transit districts, and then he clusters to find the transit districts and then tries to say "look at all the transit districts I combined", when in reality the ones he's combining are tiny and inconsequential.

If he wanted to do something, he should demystify clipper card purchases. Every agency has its own bespoke fare system, and its complete bullshit if you transfer between systems. THAT would have been interesting, especially given how these things interact with agency funding.

</comment><comment><USER8> Apologies for playing devil's advocate but in areas where there are few riders, would it not be a reflection of poor transit service in the first place? I would assume if the service is so bad in those areas that ridership would be poor but you'd still need to check out whether the actual residents in those areas are using alternative methods of transportation as opposed to just commute data?

</comment><comment><USER9> Absolutely amazing research!

But let's now imagine the transit systems of SF area have been reshaped according to the article. It will surely trigger a change in commute patterns. Will this change be sufficient to significantly affect the clustering? Will the system stabilize eventually?

</comment><comment><USER10> Isn't this in fact k-means clustering rather than "machine learning"?

<comment><USER6> Looks like he used a hierarchical clustering (probably single-linkage) rather than K-means.

But yes, I'm also not too keen on using a clustering algorithm and calling it machine learning.

</comment></comment><comment><USER11> This does not take into account potential riders, am I correct? This seems to be a common pitfall when planning new routes or systems.</comment>