skysight-inc/HackerNews huggingface dataset:
This is a really cool problem. I don't claim to understand it, but here's one way of thinking about it. The paradox assumes that when we see the value of money in the envelope we open, we get no information about whether that's the smaller or larger amount of money. Now, in practice, is that possible?

Let X,Y be i.i.d. draws from some distribution with CDF F, and say we see Y=y when we open our envelope. If the distribution satisfies the constraints of the problem, then we have to have that, for all possible values of y:
P(X > Y | Y = y) = 1/2 = P(X < Y | Y = y)

In practice, this is impossible. The reason why this is impossible is because P(X>Y | Y = y) = (1-F(y)). Since F(y) is a CDF, if we take the limit as y goes to infinity we have that (1-F(y)) = 1. So (1-F(y)) can't equal 1/2 regardless of y. That is, the probability that the other envelope contains the larger or smaller value is not independent of the value we observe in the envelope we open. And, more importantly, it can't be, such a distribution doesn't exist. You have to consider the sampling distribution to get a meaningful calculation.
Oddly enough, the Economist (not a publication given to Luddism) expressed the same worry a couple of weeks ago, noting that the conspicuous disruption of some sectors has not yielded the huge economic productivity gains one might expect: http://www.economist.com/news/finance-and-economics/21583615...
http://forums.freebsd.org/archive/index.php/t-27111.html
Herman Hesse "The Glass Bead Game" is incredible. For great mind fucks, check out the crime fiction of Jim Thompson: 1st person, you're a petty crook, dumb & scared, people trying to kill you are right behind you, and most the books end with you being caught and killed in the last sentence. It takes a day or two to shake off his books' reality.
Folks, it's an analogy. An analogy compares two different things... trust me, I know they're different and I know in which ways.

All I was saying is common sense doesn't get you far in the Monty Hall problem. It really doesn't:

>[Vos Savant] received thousands of letters from her readers; 92% of the general public, 65% of universities, and many with PhDs, were against her answer.

Thus, it's kind of silly to say we're wasting time by going past a common sense analysis of something. It's also revisionist to say common sense does help you solve Monty Hall.
Executive Decisions - Two brief examples of tough decisions a CEO has to make.
No, not my site at all. Completely agree it's ridiculous though :)
> Kidnapping is essentially nonexistent in the US today.

Wow! I wasn't going to bother replying, but this is egregiously wrong:

http://en.wikipedia.org/wiki/List_of_kidnappings#2000-2009

There are scores of kidnappings in this list, and it only covers ten years.

> Nobody would say "ho-hum, it's just another celebrity kidnapping story..."

But by wrongly thinking that "Kidnapping is essentially nonexistent in the US today", you did just that.
It's not my site. I'm not sure how the numbers were done, but if you refresh, they're...moaned in a new way.
Thanks, that is a wonderful way to put it. The swaps are not independent in their effects. That satisfies me.
Agreed that it's a net loss in legibility, but it does improve spatial reasoning. In a single window environment like iOS, there's a definite hierarchy: the home screen lies below apps which in turn lie below the control panel/notification window. Being able to see the blurred contents of the view below e.g. the control panel really helps reinforce that and stops the user getting lost in the OS, though admittedly at the cost of legibility. It's a fine line to be sure...
AFAIK ports checks the checksum of the file when it downloads it against the checksums the ports maintainer submitted.

For the ISO mirrors, I don't think there's anything automatic, you have to manually run sha256 on the file and compare checksums. Do Linux distributions have another way?
Kazuo Ishiguro is a favorite: Remains of the Day, Never Let Me Go
I think it's actually about 1^-12. Given that you have N doors, you (N-1)/N chance of picking a door with a goat. If the host then shows you another door with a goat, and you decide to switch, then you have 1/(N-2) odds of picking the door with the car. So your overall probability of picking the door with the car if you switch is (N-1)/N * 1/(N-2) = (N-1)/(N(N-2)). For N=3, this is 2/3. For N=10^6, this equals roughly 10^-6 + 10^-12. So you have only a 10^-12 margin over the original 10^-6 shot of picking the car.
It sounds like some amazing performance boosts around networking. I wonder how much of that will carry over to all of the network-type appliances built on FreeBSD? I know Juno's OS runs a pretty ancient version of FreeBSD (6 or 7 IIRC), but am not sure about any other commercial uses.
I myself understood the problem with Afforess's reply. You are explicitly pinning the value in the envelopes, but remember the other envelope has either half or double of the value than the one in your hand, and this is the crux of this paradox. Hopefully, I am thinking in correct terms.
I hope there's plenty of other reasons to give gdx a few extra points, at least compared to Cocos2d-x. Being able to write your game for desktop, iOS and Android with Scala or better performance than Cocos2d-x for example. SCNR

Glad to see other Android "old-timers", would love to see what you came up with back then.
Arrow's theorem does not mean what you think it means. All Arrow's theorem says is that it's possible for a rock-paper-scissors style cycle to exist among the top preferred candidates.

Arrow's theorem most certainly does not mean that for every advantage a voting system has there must be some sort of corresponding disadvantage, nor does it mean that "all voting systems are unfair" or that "all voting systems have similarly bad problems".
I guess I skipped a lot of background knowledge :)

The quantity everyone is arguing about is 'the expected gain from swapping envelopes' (http://en.wikipedia.org/wiki/Expected_value). Informally, you might say 'the average gain from swapping envelopes'. The way you work this out is you take all the possible things that could happen and for each one multiply the probability of it happening by the amount you gain if it happens. For example, suppose we play a game where I toss a coin. If it's heads I give you $2 and if it's tails you give me $1. Your expected gain from playing this game is:

E(Gain) = P(Heads)*Gain(Heads) + P(Tails)*Gain(Tails)
= 1/2 * $2 + 1/2 * -$1
= $1 - $0.5
= $0.5

If you play the game repeatedly, your average gain will converge to the expected gain ie if you played the game a million times you would win pretty close t half a million dollars. That's called the law of large numbers (http://en.wikipedia.org/wiki/Law_of_large_numbers). That's why we care about expectation - it tells us what would happen on average over large numbers of repeated trials. It's also very simple to calculate and quite intuitive to reason about.

In the case of the two envelopes the problem comes from the fact that there are an infinite number of possible amounts in the envelope. It turns out that adding up an infinite series of numbers doesn't always behave the way you would expect eg

1 + (-1 + 1) + (-1 + 1) ... = 1 + 0 + 0 ... = 1
(1 + -1) + (1 + -1) + (1 ... = 0 + 0 + 0 ... = 0

In the example above we are adding up the same numbers in both cases, but depending on how we group them we get different answers. The same thing is happening in the envelope problem. The different arguments in this thread are just different ways of adding up all the possible cases and they get different results. The actual problem here is that the theory of expectation only applies when the sum is well behaved (http://en.wikipedia.org/wiki/Absolute_convergence).

Because the expectation is not well-defined for the envelope problem the law of large numbers does not apply either. If you play the game millions and millions of times your average win per game will not settle down but will keep jumping around forever.

Like the Monty Hall problem (http://en.wikipedia.org/wiki/Monty_Hall_problem), it's interesting because even expert mathematicians often get the wrong answer if they don't carefully work it out step by step. It shows the value of having a formal system of probability to back up intuition.
IOS Toolchain based on Clang (LLVM) for Linux
I live in the area and I am friends with teachers within the school district.

I see this article as a fluff/pr/sales bit of writing. The article states nothing about the tech or who supplies the names of the children to be watched. Most of the people on HN can guess the tech. Who is giving the ID of the targets is the interesting bit.
Or you get a couple of creative and well connected kids to get a sizable number of other kids to spam keywords as a joke.
It looks like the main use of Dropbox is just as a mechanism to upload to their service. To be fair, this is a lot easier for an end user to deal with than something like FTP, SFTP, and especially git.
> decreasing accessibility

Scheme is super-easy to set up these days.

Step 1: Download http://racket-lang.org/

Step 2: Follow the quick start guide: http://docs.racket-lang.org/quick/

Step 3: Click "Run"

No "click through Visual Studio's project setup" phase, no "how do I open the text editor from IDLE" phase, no "open a command prompt" it's all right there.

This makes the environment and the language perfect for beginner students.
I know from past threads on this topic that I am not the only person here who has found Robert Pirsig's work worthwhile. I mention it because it is currently on my nightstand, for the first repeat visit in too many years.

http://en.wikipedia.org/wiki/Robert_M._Pirsig
Javascript simulation (might freeze your browser so would be a good idea to run it in Node):

var t = 100; for (var i = 0; i < 1e6; i++) { if (Math.random() > 0.5) { t = t * 2; } else { t = t / 2; } console.log(t); }

It's interesting how quickly the return goes from extremely small to extremely big amounts.
Hurry App - URL based countdown application for launch dates and more
So, it saves you the extra click to upload via SFTP? I really am not sure I get the point. Are they targeting people who are confused and befuddled by normal file synchronization?
The two books I have active right now:

From Falling Bodies to Radio Waves, Emilio Segre
A River Runs Through It, Norman Maclean
Hmm, I've heard of React, but have not had a chance to look at it much or use it yet. Looks like it would be better than any of the other alternatives out there though for PHP with a similar feature set. Thanks for the recommendation.

MySQLnd uses the same API as MySQLi, so the only differences are deciding which to use within php.ini file and ability to use the asynchronous methods in for the MySQLi API in PHP. When MySQLnd originally came out, there was no support for SSL connections with it, but that's been fixed since PHP 5.4 I believe.

Won't be able to use PDO though if wanting to use the async stuff (unless they have added that). Could probably write a small adapter to wrap one or the other though. MySQLi API design is kind of quirky compared to PDO API, so I generally write a small helper class to make life easier for dealing with prepared statements and binding variables to them.
ooh, i'd like to mount her device.

...

i'll show myself out.
Reminds me of http://www.welcometothescene.com
What about some kind of artisanal steak, locally-curated by genuine Brooklyn hipsters? Or Kobe beef - those cattle get massages!
And another and another, all of them grey.
Thanks a lot for the info. And yeah I'll definitely contact you if I do end up moving there!
Way back in the late 90s I had DirecTV and lived in a place that would fry anything with a phone jack if it wasn't unplugged during a thunderstorm. Lightening got the DTV box's phone circuitry (the rest of box worked fine) when we weren't home, and I didn't want to buy a new one. A buddy showed me how to hack the card with a reader/writer, and I was into the scene for a while (I continued to pay DTV their money each month; this was a hardware fix, not payment avoidance). It was fun working on something at such a low level. Far smarter folks than me were doing the actual hacks, but I had a grasp of what was going on. Very simplistically, the card acted like the cable TV filters on the side of your house, deciding what the box would and would not decode for your viewing pleasure.

By the time Black Sunday rolled around, I had purchased a new box and gone "legit". But I did read about it, and was impressed by a very cleverly put together and well-timed hack to make all of those cards go poof. What TFA doesn't mention, and maybe I'm remembering it wrong, was that it was the hacks themselves that did the cards in. DTV couldn't rely on their code to be there, since the hacks modified it. So DTV anticipated what the hacks would be, waited for them all to be in place, then pulled the trigger. IOW, the hackers indirectly did it to themselves.
Yes, you can. The thing is that Github is still intimidating for a lot of people. They can use this as a simpler alternative.
Install W3TC[1], enable all the caches. Test to make sure it doesn't screw up your CSS and JS. Problem solved.

[1]: http://wordpress.org/plugins/w3-total-cache/
The only problem with DANE is that it doesn't protect from NSA. You are simply moving trust from CAs to your TLD owner. Whoever controls your TLD (and whoever can subpoena them) is able to change your zone file without you realizing it.
WTF?? So,, yes,, use double-commas to drive home your point since you must have had some reason to put them there.

My point is that you would be quite right to reject writing in which someone employed double commas as an affectation. Just because a writer thinks it says something special does not mean readers have to agree.
The article is from 2008, the actual event goes back to 2001.
> Is there a workaround?

Not that I know of. I added a note to the README about it sending lots of emails to help others avoid accidentally doing this, though.
The Real Reason Creative Workers Are Good for the Economy
Wool by Hugh Howey
A Device for Women-in-distress designed by Indian University
If someone put a simple UI in front of github pages, I think they'd have a winner...
I went of a bit of a Murakami bender after reading The Wind Up Bird Chronicle. While it's still my favorite of his works, Kafka on the Shore is pretty fantastic as well.
either you have confused me, or it is _you_ who is confused.

i think it's the latter, but i'll see what other people say.

-bowerbird
Is this because asynchronous I/O calls don't work consistently well on all the platforms that libuv targets?
Yeah, that's true; DANE does not add anything to the encryption of the protocol itself.

The point of this is to, hopefully, slowly get people to start actually verifying certificates instead of just randomly assuming that they are secure.
It's legacy free in the sense that it doesn't do paravirt like Xen and requires hardware assistance like KVM. Maybe also that it doesn't use QEMU which has some pros and cons: http://www.slideshare.net/syuu1228/implements-bios-emulation.... Ultimately, it will let people like NetApp use it on their filers without any GPL complications though.

In all other respects, it's still in its infancy and I wouldn't expect KVM parity for common use cases until the next release. I'm more excited about the VIMAGE stuff in 10.
How can you host a website without paying for it? Just like fighting against "pirate" websites, just in reverse this time.
If it is possible to switch and gain on the average we could write a 10,000 or so iteration monte-carlo simulation of this switching algorithm to demonstrate the gains.

The envelope has either x or 2x. One envelope has amount z, but the agent doesn't know if z = x or z = 2x.

If it is true that not switching leads to an EV of 3x/2 but switching leads to a higher EV: then a single switch each round should come back with an average value of greater than 3x/2.

In the Montey Hall problem, we can code up such an agent to demonstrate that the naive intuition is wrong. However, in this case, regardless of how many times we switch, we still end up with an average value of 2x/3.

Therefore there is an error in the math that says that switching has a higher EV than staying.
The worst responses always start with "As a *". Haha.
In this definition from Wikipedia, in the section on Microeconomics, it is claimed that perfect information is a physical impossibility.

Can you help me understand why free markets "by definition" require that which cannot exist?

http://en.wikipedia.org/wiki/Perfect_information
This is a fantastic and subtle paradox, and not at all taken to quick resolution. A resolution follows, first to spot a problem (if there is one) gets a cookie.

Consider the amount in the lower to be f(x), the higher to be x, given f(z) such that f(z) < z for all z. In this way we generalize to all distributions, as the problem clearly applies to all distributions. You open the first envelope, which contains A. The second envelope contains B. The challenge is to calculate the value of B.

First we must calculate x. The chance that A = f(x) is 1/2, the chance that A = x is 1/2. The average value of A is (x + f(x))/2, so the average value of x is [f+I]^{-1}(2A), where I is the identity function and [g]^{-1} denotes an inverse function.

Now we calculate B. The trick lies in this: both calculations must lie in the same reference frame. So B = x with probability 1/2, and B = f(x) with probability 1/2, giving us B = (x + f(x))/2.

The rest is plug-and-chug: B = ([f+I]^{-1}(2A) + f([f+I]^{-1}(2A))/2 --> B = [f+I]([f+I]^{-1}(2A))/2 --> B = 2A/2 thus B = A.

Therefore over all probability distributions that can be defined we have the average value of B equal to A in any case. A purely mathematical resolution is satisfying, but I am not in any case an epistemologist, so it may not satisfy people who take a different interpretation of math than me. It works, and I like it.
If you want to learn more about this sort of thing there is an excellent textbook which teaches probability theory using randomised algorithms (eg uniform hashing, load balancing, queueing theory etc).

http://www.amazon.com/Probability-Computing-Randomized-Algor...

It's one of my favourite textbooks and it's full of powerful methods and intuitions for any programmer.

NINJA EDIT PLUG: If anyone wants to work through that book I would be more than happy to help out and answer questions (jamie@scattered-thoughts.net). I wouldn't mind a refresher myself and I've always found that explaining things to other people helps clarify my own thinking.
Sorry for misunderstanding you. I guess I lacked a bit of common sense...
While I often read Science Fiction and recently enjoyed Corey Doctorow's Rapture of the Nerds, Last week I finished Jeet Thayil's Narcopolis.

Currently, I am reading the third volume of Rick Atkinson's history of the second world war, The Guns at Last Light: The War in Western Europe, 1944-1945. I've enjoyed all three volumes over the past decade.
I'm surprised no one's mentioned Philip José Farmer and his Riverworld series. The last book is comparatively weak, but the rest are great.
The favicon's are the same - rebranding?
Most Linux package managers use GPG signed packages.
Go ahead and run a few million simulations of the problem and graph the running mean over time. You might be surprised :)

Be sure to use exact arithmetic (eg http://docs.python.org/2/library/fractions.html)
Considering that iOS 7 is taking UX cues from android and jailbreaking, I don't understand how you can say that.
In particular, perfect information is required in order for the free market to allocate resources efficiently; if obtaining information has a cost, there are all sorts of fun ways to abuse that in order to break competition and misallocate resources. You can see this in the US cellphone industry - by increasing the complexity of their plans, cellphone providers have made it more expensive to comparison shop, meaning that customers (rationally) go with the first option rather than the lowest-cost one.

You can also see this with some of the smaller-scale Ponzis and investment scams - so long as the amount of money each investor has invested is much smaller than the amount it'd cost to investigate the investment, it's not rational for them to do so. One of the recent US Ponzis, Perma-Pave, actually failed because they got greedy and took on a large investor with reason to investigate what had happened to their money.
Do people actually let GitHub emails go to their inbox? After they got really aggressive about signing me up as a "watcher" to repos I found it necessary to just route all GitHub email to a a dedicated folder that I never read, then only whitelist repositories I actually care about.
Couldn't agree more about Cryptonomicon.
I was about to send a PR for the README, will save a few folks some headaches.
tl;dr -- the article is lightweight technically but touches on important and potentially flawed aspects of the government's relation to IT security industry.

Formatting aside, the content is relatively important in a non-technical way. It is detailing the manner in which the USG is experiencing some brain drain due to both its policies and image. I wish the author had contextualized the Miami conference a bit better (and the Fedora comment is hardly forgivable, I hear Windows 8 is used in China too). There really is a need for some US cyber policy but I fear that in its current incarnation that the government is not well suited to bring on the kind of infosec talent that it needs. Yes there may have been excesses (I think I saw one or two Snowden articles on HN) but there are real attacks going on against both USG networks and those of prominent US companies. With all the people on here who are US based entrepreneurs (aspiring or succeeding) I think we want some level of government protection against foreign government attacks, in the same manner as brick and mortar businesses don't want tanks rolling through their walls.

I just hope that the US as a country consisting of both public and private sector can reach a point where petty (rather outdated) regs don't prevent willing top talent from helping the government while simultaneously ensuring that US tech companies don't fall into being simple fronts for USG collection.
What, because "Mid-70's" isn't the same as "1981"? It sometimes takes a little while for the ripples to be felt.