skysight-inc/HackerNews huggingface dataset:
Original author here, the adding an index on every column is very much a joke. A better solution would be taking advantage of pg_stat_statements in Postgres 9.2. It normalizes all queries which are run and tracks total time spent in your DB on those queries, this would be a clear way to determine where indexes can likely improve your performance. There's actually an earlier post I did which talks a bit more about this - http://www.craigkerstiens.com/2013/01/10/more-on-postgres-pe...
Must be some special circumstance on that more to that story than meets the eye.

This info pertains to NYC, I believe it to be correct:

http://everydayaperture.com/law/

More info:

http://www.bobatkins.com/photography/tutorials/photography_l...
I'm a little rusty on this subject (I might come back later and link some sources/videos), but my main issue is not with HFCS vs table sugar, but just the fact that HFCS is in everything nowadays. This is partially because of corn subsidies by the government (which makes HFCS cheaper than its "actual" price). However, this is also because at one point in this country we decided that fat was bad (with a bad study), and we thus took it upon ourselves to remove fat from our diets, and in fact largely succeeded. Yet all the things we were trying to prevent (like heart disease), went UP. What happened was manufacturers replaced the fat in many products with HFCS. Its to the point now where you go to the store and many brands of bread contain HFCS, its almost inescapable. I certainly don't want that replaced with normal sugar, I just want the price of HFCS to be accurate, and for the government to stop making drastic declarations in nutrition that can lead to these really strange and unexpected consequences.
The quotes around 'natural' presumably.
Hey, have the source while you're at it - http://github.com/nddrylliog/thechoice

You only get to experience it once though - once you spoil it for yourself, it's spoiled. Choose carefully.
I think s/he means "HF", "CS" and "natural" since you're not actually quoting anyone
I got stuck on the crime question, and cheated. They're pretty difficult riddles! It wasn't immediately clear a hint would appear (after my first 6 answers).

Now I'm stuck in the door. Its interesting and somewhat fun, but I'm not sure I have all day to fail fail fail fail fail. Perhaps you could share your dropoff metrics once you have more data.
A house will have just one postcode.

- Not if it is a new build, had a temporary postcode during construction and has since been assigned a new postcode.

(In the UK) an address will contain a county.

- Not if it is in London (city and administrative county).
I don't understand, they take a distribution known to look like a normal distribution, then... yep it looks like a normal distribution, central limit theorem proved.
Six ways Apple should open iOS | The Tech Block
Stress, A Matter Of Judgment
It's since become a corn product protection racket, I believe. And probably due to pork barrel politics in the Midwest
It's the same molecules. Like everyone else has noted, 1 sucrose molecule = 1 glucose + 1 sucrose. The proportion of glucose to fructos is just slightly different in HFCS vs table sugar (55/42 or 42/53, versus 50/50).

To your correlation/causation point, why don't you think that this is the result of having massive, inexpensive, and domestic sources of a molecule that makes the human brain want to eat more? Rather than some minor distinction in the ratio of the monosaccharides its composed of?

Sugar is basically a drug with immediate gratification with only longer-term side effects to the health. Unless there are laws, companies that put the most of it in their products will 1) make more money because it's cheap and 2) sell more product. I don't know what happened in Canada, but I would guess either those interested in profiting even at the expense of public health either out-competed more ethical competitors or were able to weaken public health laws. Who knows, maybe the US public was the first target, and they went to the north only after our pancreases/adipose tissues were completely saturated...
Uh, theres no hard and fast rule for how colour blind people see. I'm colour blind and I can quite clearly see the difference between the top set of buttons.

It's really difficult to talk about, because obviously when I use the simulator, the colours look really messed up and don't make sense but that's already equating in my colour blindess, but I imagine it's a lot more subtle for the vast majority of those who are colour blind and therefore it's hardly 560 million people.

I honestly don't think the wins would be worth the losing green/amber/red standard that most people instinctively understand and have had their eyes grow used too.
Success is grey Warning is yellow...
I don't see how this is a problem ... or something to be worried about.
Or: Design systems, not features.
Yup, would've added more analytics if I had the time - consider this a first foray into the world of "let's teach people stuff without them being even aware of it because they're caught in the story".

Hopefully! This is an experiment. Expect next episodes to be in increasing order of difficulty... Episode 2 is about deconstructing the game...

Btw, hints drop if you fail more than 5 times at a question. Just putting that out there.
This is like the programming version of the Portal games.
Very cool. What are you using for the voice synthesizer?

Also, I'm stuck on a bug: When I hit command-enter after typing "open @left", it spawns a new window with http://thechoice.amos.me/[object%20Object]. (Chrome 27, Mac 10.8)
I can't quite decide whether hiding the stupid with SSL would be a good thing or not.
If done properly (incl. pinned cert(s)), it would mostly hide the stupid, which would help protect users - but also make it less likely that users would ever know just how bad the app is.
Down-voted because this has nothing to do with the article, which is about the US sugar protectionism racket and not the health implications of HFCS.
In the spirit of a vm in a vm, has anyone successfully compiled emacs in emscripten yet? I ran a quick test yesterday and it didn't go cleanly.
El falso secuestro
I'm more willing to trust Rob Pike on his assesment than a random Internet comment from someone who has neither knowledge of Go nor has read the comments on their mailing list.
Even though too much refined sugar is bad for you (there was very little tooth decay before 1850), I don't like ingesting HFCS because it makes things taste horrible. It doesn't taste the same as sucrose, which has much better flavour.

OTOH the more things have HFCS the fewer sugary products I eat, which is good for my health. Wouldn't work if everybody did that, of course.
High Fructose Corn Syrup is not always 55% fructose. HFCS can vary greatly in that ratio according to [this USC study](http://www.ncbi.nlm.nih.gov/pubmed/20948525) that analyzed the fructose ratio of a variety of HFCS only sweetened soft drinks.

They found the actual ratio varied from 47-65%, with the mean amount being 59%, and the amount in several major brands was 65%.

The fructose ratio in HFCS is not regulated or reported, so you could be drinking anything. With a mean of 59% a 9% difference to table sugar is a big difference, and many popular brands have a 15% difference.

According to the study, the difference between HFCS and sugar is not a myth.

The other advantage that sugar has over HFCS has nothing to do with the chemical composition. It's more expensive.
I liked this but as other commenters have pointed out it's purely binomial at this stage. The great thing about the central limit theorem is that it is more general than just the limiting Binomial case.

So, there's this thing called the cumulant-generating function. It's pretty much defined for any random variable X. If you want to get technical it is the logarithm of the Fourier transform of a probability density function f(x). You're on HN so you probably know the first two jargon words, "logarithm" and "Fourier transform". A "probability density" just means that f(x) dx is the probability for X to be in the interval (x, x + dx). The Fourier transform puts us into a "frequency space" indexed by some variable k, so we can write the CGF as some function c(k), or in other words:

c(k) = ln[ ∫ dx f(x) exp(i k x) ]

So for the "step left/right" variable which is -1 with probability 1/2 and +1 with probability 1/2, c(k) = ln[cos(k)]. (It can get a little messy when you ask what happens when cos(k) crosses 0 etc, but this function is infinitely-often differentiable on a disc centered at 0 which is all that we need.)

It also turns out that since the sum of all the probability ∫ dx f(x) = 1, you can just evaluate this for k=0 as c(0) = ln[ 1 ] = 0. The cumulants are derivatives evaluated at k=0:

c'(0) = i E[X] = i μ (where μ is the "expectation")
c''(0) = - (E[X²] - E[X]²) = -σ² (where σ² is the "variance")
c'''(0) = -i E[(x - μ)³] = -i σ³ γ (where γ is the "skewness")

It is not very hard to prove that if I have a sum of two random variables X + Y = Z, then their CGFs add like cz(k) = cx(k) + cy(k). This is the Fundamental Awesomeness of Cumulants: cumulants are pseudo-linear; they're linear in independent random variables.

It is also not hard to prove that if I have a scalar multiplication U = X / n, then cu(k) = cx(k / n). Combining these together, the mean M = (X1 + X2 + ... + Xn) / n of n identical and independent random variables looks like:

cm(k) = n c(k / n)

Now if you know calculus, you know the rest. Taylor-expand around k = 0 to find:

cm(k) = i μ k − k²/2 * (σ²/n) − i k³/6 (σ³ γ / n²) + ...

We see a geometric attenuation in this series, we keep dividing new terms by n. If we drop terms from c'' on we get a constant, M = μ. That's boring, so we keep one more term, to find:

cm(k) ~= i E[X] − (Var[X] / n) k² / 2

This is extra-good if f(x) is symmetric about the mean (so that the skewness vanishes), but it is also pretty good even if the distribution is skewed.

We can now invert all of the steps to return back to a probability density: you exponentiate, so you get exp(i μ k) exp(- k² σ²/ 2 n), then you inverse-Fourier-transform, which transforms the exp(i μ x) into a frequency offset x → x − μ and which transforms the Gaussian into another Gaussian, so you get a Gaussian centered at x = μ.

In other words you get approximately a normal distribution with mean E[X] and variance Var[X] / n, with the error given by convolutions of higher-order terms, and the first correction disappearing when the distribution is symmetric about μ (or otherwise non-skew).
As I was completing the fly the Numans problem I felt kind of dirty because I thought I should really be using a for loop of some kind.
I live in the Bay Area, so this hits close to home.
See, that's a very interesting "bug" that was reported to me before.

Here's a little behind the scenes: your answers are actually CoffeeScript that get compiled on the client (along with some support code for each question) and eval'ed.

Since window.open is defined, that's what's happening here.

The commands you're looking for, for that question, are more along the lines of 'enter'.

EDIT: for voice synthesis: speaker.js - an Emscripten-compiled version of espeak. It sounds crappy, which is just a perfect casting for this voice.
How we use GitHub as a killer bug tracker and code review tool
Noticed that too. Maybe the author is colorblind for those? Maybe we are?
Thanks for the advice. Trying to get my first gig. :)
Things Startups Can Learn From Reading ‘One Piece’ Manga
I was thinking the same exact thing. I'm color blind, and Success and Danger look very close while Success and Warning are easily distinguishable.

EDIT: After another read, I see that it was a typo in the article. That being said, is Primary not already blue? I'd venture a guess that it's actually purple (again: color blind) if the OP is suggesting making Success blue.
Wow, I never realized this was such a heavily utilized feature. Do the devs out there test for zoom compatibility? I kinda have on and off but hadn't given it much thought.
I don't think that "which sugar" is better is necessarily the debate that is going on here. It is the protectionism of the sugar industry with a huge amount of money going to waste because of it.

---

Honestly, the amount of sugar/HFCS in various products in the US is absolutely insane. Hell, I pay a premium to buy whole natural peanut butter compared to Jif or the other crap which all contain sugar.

These days I spend more time looking at labels trying to find out what crap is in my food that shouldn't be there, chemicals, sugars, all kinds of salts, and preservatives. Ugh.
I'm about to start attending meetups and other events, so with some networking and meeting new people that may help me out.
Hey, if you know CoffeeScript and feel confident, everything is fair game.

The game is supposed to be accessible to non-coders as well, hence all the hand-holding.

If you feel frustrated because the first chapter is too simple, you're gonna like the next ones...
Should check out the colour blind checkbox for l4d2. Works for me, and doesn't the change the colours from one to another (in the sense that I call different shades of red, red. :P ).
for the door question, you should support:
open @door, @xzoor.askKey(@door)
Monte Carlo Simulations in Tennis
Come help us hack the Auto Industry - full stack engineer at CarWoo (YC S09)
We are looking for an awesome full stack Rails developer to help us take the online auto industry by storm. You'll join a great engineering and design team that's working hard to bring car-buying into the 21st century. The features you create will help turn the mostly terrible experience of buying a new car into a wonderful experience for our customers.

Responsibilities

Work with David, Tommy, Erik, Scott, Rimas, Tim, Derek, Jeremy, Peter, Adam, Jon, Todd, Matt, and Patrick to create a world class set of products. We're a small team, but we work smart and get a lot done. Here's some of the cool stuff we're working on right now: a queuing system to optimize our operations across the country, mobile apps, application of game theory, and a lot of other great things we can talk about when we chat.

You'll get the chance to work on any or all of this stuff if you so choose.

Qualifications

- Deep knowledge of Rails and everything that goes along with it (MVC, REST, relational database design/SQL)

- Solid grasp on modern web application design using Javascript, HTML, CSS

- Extensive Javascript experience outside of JQuery (Backbone, node.js)

- Experience with version control systems (we use Git/Github)

- Solid testing methodologies and willingness to write comprehensive tests before release

You get extra bonus points for:

- Extensive Javascript experience outside of JQuery (e.g. Backbone)

- Ability to write complex SQL

- Understanding of good RDBMS design. Experience optimizing queries.

- Experience with memcached, sphinx, and nginx

- Story-driven development

- Web service/API development (REST)

- Ability to play ping-pong skillfully and/or drive a go-kart furiously

Perks

- Full Benefits (medical, dental, vision, 401k)

- Unlimited PTO

- $5,000 to buy anything you want to get your work done (must include an Apple computer of some sort)

- Competitive salary and equity in the company

If you're interested, send an email with your résume and something interesting about yourself to david@carwoo.com

We're based in Silicon Valley, but if you live outside the Valley, we still really want to talk to you (we'll pay for your flight, hotel, and meals when you come interview with us).
> "Polygamy" may have become gender neutral in technical circles, but I doubt the general population have caught up yet.

The thing is that virtually all polygamy that has existed in the real world is polygyny, so the distinction between that gender-specific form and the general form (as well as any reference to polyandry) is of almost entirely of theoretical/technical/specialist interest.

> Also, "polyamory" doesn't have the notion of marriage in it. Maybe that could be a useful distinction.

I think it is.
I've already graduated at this point; I had to write a thesis, but when you've got two interesting projects going on at once, it's hard to say which is the "procrastination." My point was more that the programming projects "have not moved forward in a long time", but this isn't, I think, because they are somehow boring now that I've got the "hard part" solved. (I viewed the original post as warning about such a thing.)
Which is sad, because I've found Medium to be a terrific blogging tool for people who don't want to be full time bloggers.

The interface is really very easy to use, with the only annoying thing being the difficulty in browsing Collections when deciding which one to post your work in.
> In probability theory, the central limit theorem (CLT) states that, given certain conditions, the mean of a sufficiently large number of independent random variables, each with a well-defined mean and well-defined variance, will be approximately normally distributed (i.i.d.).

No, that's just wrong. The context is some positive
integer n and values of some n real valued
random variables independent and identically distributed
(i.i.d.).

If for some n do what the quote says, then
are not guaranteed to
get a Gaussian.

Moreover, if do what the quote says and take the limit
as n goes to positive infinity, then, say, in the case
the random variables have expectation that is finite and finite
variance, will get
just the common expectation of those random variables --
this is the law of large numbers, not the
central limit theorem. That the distribution
of the mean
converges to the point with the expectation is
the 'weak' law of large numbers. That the
mean
converges to
the expectation with probability 1 is the
strong law of large numbers.

For the central limit theorem, add up the n i.i.d.
values and divide by the square root of n.
Then under meager assumptions (e.g., i.i.d. and,
for likely the strongest conditions known,
the Lindeberg-Feller conditions), as n goes to infinity, the distribution of the result will converge to
a Gaussian ('normal') distribution. Authors with
the details include J. Neveu, L. Breiman, M.
Loeve, and K. Chung.

It's essential to divide by the square root of
n, not just n.
You're still missing the point. :) Repeated face-to-face conversations with experts and other students (i.e. a classroom learning environment) is not the same as sitting alone, in the middle of nowhere, in front of a computer.
I used to like Coke in the UK but then I think they switched. Night and day indeed. Great news for my health, though!
Dude, let me quote something:

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.

People have a fsckin' right to eat unhealthy and who the hell are you to fix prices of their food so that they can't?

That's one thing. Another one is that such schemes are really, pragmatically bad as they make people involved in them make political decisions which protect their unfair advantage at the cost of goals important to the general public. Do you really want people to vote for whomever promises to pass bills giving them most benefits at the cost of others? Well, I know that people sometimes do that anyway, but IMO it shouldn't be encouraged with successful examples lasting for two centuries.

And at last - people are pretty capable of getting what they want. If you make it slightly more expensive, they'll simply pay. More expensive - they'll switch to worse alternatives (HFCS, anyone?). Even more - illegal production. Outright ban - sugar mafia. I mean, the US already tried to "fight alcoholism" some time ago and it almost worked.
Spectacular. How'd you do on conversions?
Absolutely. I actually use a Firefox Addon to rebind some of the keys so I can zoom by pressing +, - and reset it with *.

Text is usually not the problem, but images and thumbnails are. I rather zoom in to see the thumbnail up close instead of browsing to every site that is linked via one.
Libogg and libvorbis compiled to JavaScript
Thanks for the feedback.

See https://news.ycombinator.com/item?id=5795893 for context - window.open gets called on 'open'. If any HNers have ideas for restricting what gets called, I'm all ears.

Source is on GitHub, at https://github.com/nddrylliog/thechoice
> Except since this isn't a standard procedure, they can charge whatever they please for the testing and prep - why do you think a doctor won't make money with fecal transplants?

Is he allowed to, either by law or his malpractice insurance?
My solution to the "what to print" problem is construction toys. (The current crop of consumer-grade printers are already good enough for this.) I'm creating an entire toy system ala Lego Technic that's meant to be printable. I call it "bitbeam". I'm spending this Summer doing customer development to figure out which kits to design.
I think this would be a lot more powerful if you had some info on consequences of sleep debt.
I have eaten stuff with Stevia, not sure what it is about it though, but it causes my muscles to ache.

I can be completely fine, eat something sweetened with Stevia and about an hour or two later my muscles will start aching. It is worst in my shoulders :-(.
There are lot of 3rd world countries in which I'd rather be a poor person than Texas.

Your governor believes many (if not most) Federal assistance programs are unconstitutional. He believes in drug testing for the unemployed.
It is - we're in the process of transferring the hostname to the ASF and it's somewhere in between right now. Fun. But you can still get at the pages - http://jclouds.incubator.apache.org/ is the current site, which jclouds.org should be redirecting to.
Sorry, I wasn't clear (and I think I meant "unlock", not "open").

I meant that you should support skipping temporary variables.
Great idea, but I'll just leave this here:

http://en.wikipedia.org/wiki/Sleep#Optimal_amount_in_humans
Especially when it can be made from things like Switchgrass or from industrial byproducts like saw dust and wood chips.
No Fee if you're accepted
This is tongue-in-cheek, but find a doctor who has kids.

Once you become a parent, poop becomes Just Another Thing. :)
It congratulated me for sleeping 23.999 hours/day.
The whole damn page is 13 MB. It took over a minute to load on my 1.5mbps bandwidth-capped WiMax connection. The tab in Chrome is using over 200MB of memory on my Mac. With chrome using the maximum possible screen real estate, I can't even read the title on my 1440x900 mbp. http://cl.ly/PK8o

A+
Letter from Loretto - A Prison Letter from a CIA Whistleblower
While sucrose absorption is certainly slower than pure glucose absorption, the amount of sugar that eventually goes into your bloodstream is equivalent, and the energy yield is also roughly the same (splitting that one glycosidic link isn't really that energy-intensive).

I guess an argument could be made that fast-acting monosaccharides are more problematic for diabetics since their bodies can't deal with spikes easily, but for the rest of us there is really no (scientifically accessible) difference at all. Our food just contains too much readily accessible energy.
While reading 1000 years on english history on wikipedia one day, I was thinking of a game just like this! I really like the whole legacy and bloodline idea. I hope they have a historical recap so you can see the epic history of your kingdom.
HardwareSummerCamp.com, but it's the same information.