skysight-inc/HackerNews huggingface dataset:
Humans are demonstrably terrible at long-term risk analysis even when given full information. Hence, helmet laws. But we are even worse when we do not have full information, and when it comes to medicine, it's often not possible for us to even be fully informed. Personally, I don't want to have to ask my doctor what kind of clinical trials a drug he's prescribing has been through. If he gives me an antibiotic, I want to know that it has been approved by the FDA.

If you have a condition that there are experimental treatments for, try to get into one of the clinical trials.
I think the only way for this to not be meaningless is to have some sort of industry standard, along with accreditation programs and so on.
53 characters is certainly an "odd" length for a base64 string, as base64 uses four characters to encode three bytes.
>> Something as major as the asset pipelining feature (where you move assets out of the public folder and into the app folder), for example, seems big enough that it should be a 3.2 release not the next release after an already major change in 3.0.

What's the difference between putting it in 3.1 vs. 3.2? Is the 3.2 version number somehow more substantial than 3.1?

Also there have been quite a few releases after 3.0 - I believe the 3.0 branch is up to 3.0.8 now.
Ask HN: "Everything JS" URL
Hi,

What's the URL of a website that lists all JS technologies and explain what they do? It was featured some time ago on hn.
thanks
Another trick is to mix in the user's hashed password when you generate and check the HMAC - that way if the user ever changes their password all the previous links fail to work.
Yea we actually lost a few funjumpers because we've been so busy. Used to send 1 flight an hour with 3 tandems with 5-8 solo jumpers. Now we send 2 flights an hour with 5-6 tandems on each flight and around 2-3 funjumpers... :/ It's not always that bad but it is more often than not.

How much did you pay for AFF? You're going to be pretty sad when you hear that we do AFF for $999 :)
http://en.wikipedia.org/wiki/Sea_level_rise says 90 to 880mm, with average estimate of 480 mm, i.e. 4 feet.
So when you say it's hard not to make money with 2x the customers you actually meant you were losing money... I understand that it's marketing, but it's not making money until you get people coming back without a Groupon.
Nerds may wail and gnash their teeth but CSS3 is HTML5. Definitions change.
It seems the direct result of groupon can cripple you, much like a the slashdot/digg/reddit/HN effect for a website, but if you know how to harness the instant surge and spread it around to cross sell other products and peripheral promotions, you can ride the wave successfully.
Where do you back up your GPG private key? Where do you store the passphrase for the key? It's a long chain of vulnerabilities in any well architected system that must be addressed. This seems acceptable for a big company, but for an individual to have to go through all these steps just to protect their money seems arduous.
Agreed. Reddit's /r/fitness has consistently great stuff.

Also (disclaimer: blatant, but hopefully worthwhile self-promotion), http://www.greatist.com is a source we're building for high-quality tips, news, & general info on health & fitness.
In that case wouldn't it be better to compare London to Tel-Aviv?
Thanks for this... really interesting.

I just went skydiving for the first time last week and used a Groupon. It was fun but I wasn't immediately hooked and wanting to go again.

I paid $109 for a 15k jump that is normally $209. I bought it about a year ago (Used it because Groupon was about to expire). The facility was so packed that I had to reserve my time far in advance. (They sold 4,500 groupons the day I bought)

They tried some upselling, in the form of a video and a 2nd jump at a discounted price. The video was an additional $90, which I declined, and the 2nd jump was a "discounted" $125. This seemed kind of silly to me, as I'd only paid $109 the first time around. In the end, I wasn't upsold, so I'm presuming they lost some money on me. They also didn't collect my email address or anything. I think in the end the value you derive from a daily deal is very dependent on your ability to be smart about it (via upsells, social media, etc.).

Can you share a bit about the economics of a skydiving facility? I got the impression that the skydivers were paid per jump.

One other thought is that if I were to do it again - I've seen several Groupons for other skydiving facilities... I'd probably just buy another Groupon for another place... new view, etc. Maybe I'm in the minority but I think getting people to come back is tough when there is so much pressure from other deals.
You should keep this website bookmarked : http://searchyc.com/
"limited time of sickness?" We're not talking about a cold here, amigo. We're talking serious illness like cancer. It may very well last years, or even take the person's life eventually.
People joke about the COMEFROM statement all the time, but isn't this was observers do?
Failing Fast seems suboptimal, here.
Exactly my point. And unlike the 'Digg Effect' you get to opt in and have plenty of notice when the wave is coming.
That's easy. A "computer scientist" is a tenured professor^W^Wsomeone who does research in computer science. A "programmer" is someone who writes code for a living. A "developer" or "software engineer" is a programmer who likes business-y titles.
It seems like you worked out a lot of the positives and negatives that Groupon brings and strategized around them. How much of this planning was done from inside your business and how much was done/consulting on by Groupon reps?

Was the 30% breakage specific to your business, or was that quoted by Groupon reps as an average? I'd have to think that a Groupon for something that requires specific scheduling and booking would have higher breakage than something like food coupon.

I haven't spent too much time thinking about how Groupon effects small business, but it seems like businesses like yours are in the best position to really benefit. Jumping out of a plane is an experience, and one you're probably not used to doing. Seeing that show up in your email may spark the idea of jumping out of a plane. Since it's somewhat novel, your customers are more likely to take advantage of upsales. It's also a thrilling experience, so the customers will be pumped up on adrenalin, and more likely to be sold apparel afterwards. Did Groupon customers fall in line with normal % of customers buying apparel or did they differ?

I can really see the value to both the customers and your business in running a Groupon. However, as a consumer, I'm not going to go skydiving once a day. I'm not going to go once a week. I'm probably not going to get into trying out these adventure activities with any substantial frequency. Groupon can't just load up on these things and still provide intriguing daily deals. It seems like they have to have a mix of businesses, and some of these businesses are either not capable of strategizing around a Groupon, doing the proper measuring and acting intelligently on it, or their business model simply doesn't mix with Groupon. It's these people that are going to be most vocal with their Groupon experience and drive the bad press. Without real data (which we'll never have) we can only speculate on anecdotal reports. Even so, I see much more value in your account than another person complaining about how Groupon screwed them, or someone just running with the assumption that Groupon is railroading every small business who will talk with them.
Delaying it 60 years might help. If we ran out of oil, or started getting low by then (ie oil prices through the roof), that would be a big motivator, and help cut emissions.
This is very interesting. I think you had a small benefit because in skydiving there is a lot of things to upsell. Skydiving is such a huge, scary and adrenaline filled event in most people's lives that even the cheapest coupon hunter will have a desire to buy something to commemorate it and show it to his friends.

BTW what is breakage? Is that when people get scared and refuse to jump?
Can't find it in there. IT seems the name isnt "everything JS".
Awesome detailed write-up. Any chance I could ask you a question about this offline? My email is browser411 at yahoo. Thanks!
It'll be troublesome to fix this since any change will invalidate all existing passwords.
Hey Folks,

I'm posting this to mark the accomplishment of finishing my first ever game - Coloroids. It's an iOS game written from the ground up, with no use of frameworks or libraries. I've always been interested in game development so took the hard route as a means of forced education.

It's maybe not quite as cool or astounding as a lot of the show and tells around here but I'm pretty proud of it. I would love to hear any thoughts or feedback or even to know that somebody played and enjoyed it.

So please HN'ers if you get a chance pop over and have a look!
For what it's worth, I've personally met with 3 European angel funds in the past 2 weeks. One of which was actually government backed corporation (that had been given explicit permission to enter Israel)
If you do this in OS X animations are also slowed down. Hold shift and hit the dashboard button for a slow-mo animation.
Perhaps not quite a like-for-like case though, this one looks more like a detailed forensic "open the books" examination, rather than a chat over coffee. I'm sure there are some cases where ideas do get stolen and made successful (a bit of Googling quickly turns up Steve Blank's experience on this), but I think these examples are probably rare enough to make them noteworthy.
Actually the start ups in Israel are pretty spread out, the consequence of Tel Aviv's rent being high. Really high.
"A fondness for power is implanted, in most men, and it is natural to abuse it, when acquired." - Alexander Hamilton
Breakage is when someone buys a groupon but doesn't use it. The facility gets the money anyway.
Can Linus single-handedly block changes from getting into Linux? That just seems crazy to me if he can. I get that DHH and Linus have pulpits, but that's all they should have.

It's just extremely disappointing to hear someone say something can't get in, not because of quality, but because there's one person who doesn't like it. With that said, people do fork Linux, see Android. Do people fork RoR and actually produce versions that are used by a non-trivial set of users?
Whoever has the most firepower.
Something tells me you didn't read the article.
Sounds like a good solution. I'll have to try that out.
> Most of the farmers in my extended family are quite intelligent people, many of whom have masters degrees in agriculture.

That's nice, but are they adept computer users? I know plenty of very intelligent people who haven't needed or bothered to learn how to use a computer well. Stop seeing slights where they aren't happening.
I didn't really like cryptacular that much. I don't really know why one character of the hash is being taken off; I remember curiously wondering why that was in there when I was fiddling with the source to get it to compile on Windows.

I also don't know if that would pose as a significant security threat - sure, you would be taking one character off of the number of characters that need to be brute forced, but it is only one. I'm not informed enough to give an accurate opinion.

I do know, though, that jumping to conclusions before a thorough explanation is provided is silly... Hence why I'm not suddenly jumping to the use of cryptacular or others.
> That said, I feel that all of the Groupon horror stories floating around are from businesses that would be in trouble regardless.

First, you had it right in the sentence prior to this one. Your experience is enough of an outlier that it doesn't apply to most Groupon experiences. Second, isn't Groupon supposed to help businesses that are in trouble?
The body's incredible-- adapts suuuper fast. Among the best things to do to keep it on its toes, much like you're doing (knowingly or not!) is interval training. A helpful guide to how to do that: http://www.greatist.com/fitness/interval-training-complete-g...
Guess What: iCloud Uses Windows Azure Services For Hosting Data
To test the OP's theory, I just submitted a post with my idea for a new movie app here: http://news.ycombinator.com/item?id=2654826

Essentially its an app that allows you to report any disturbances while watching a movie in theaters. I think the idea is solid. I figure there's nothing wrong with a little real-life application of the OP's theory that ideas don't get jacked.
Can anyone think of a situation where lines of code could ever be illegal?
Toying with Moo's website at the moment and I must say, this is excellent. Thank you for the recommendation, I had never heard of them before.
Simplest, but not optimal. Ideally you'd want to settle on a mean that:

a) Maximizes arable land,
b) Minimizes climate-based natural disasters such as hurricanes, and
c) Is as near to self-sustaining as possible. That is, the global mean should not lead to significant growing or shrinking of ice caps and glaciers, nor significantly alter carbon uptake by the oceans. While some degree of human control could make up for heterostatic forces, a swing too far in either direction would quickly exceed our ability to compensate.
I enjoyed solving these. Last one is cool, but hint is too obvious ;>
I'm curious in the approximate breakdown of your expenses between other expenses and your own labor. Also, what portion of the former are fixed versus variable -- incurred "by the planeload", as it were.

I've wondered whether the businesses that can fare better with Groupon tend to be those where labor is a greater part of their expense, and where the business owners -- especially for a small business -- can effectively trade their own labor at lower compensation -- as a hourly rate or absolutely -- in return for the increased business that Groupon generates (which then provides, they must hope, a longer term marketing payoff).

Also, where expenses are variable and there is not a large fixed overhead that must be met, regardless.

Once you introduce staff labor and physical products with hard margins as larger components in the equation, it seems to me that there's less buffer with which to adapt for a mis-calculation of the effects that a Groupon or similar experience will create.

And fixed expenses have to be covered, regardless, leaving thin margins perhaps insufficient.

As you mention, you also have significant additional revenue from add-ons. And your experience, inherently, probably generates a tremendous emotional boost that in turn helps to move those.

I appreciate your detailed description and explanation of how it has worked for you. It provides some good food for thought.
As an atheist I would be seriously upset if someone said that to me while I was sick or after losing someone.

However, if you really believe it in your heart of hearts, then shouldn't it be comforting? Similar to 'they're in a better place now' -- it seems like if both people believe it's true, then it should be comforting to talk about.
>> Rails is very hard for the beginner to learn, much harder than before.

I think that Rails is hard to learn for several reasons:

* unless you've used it before, you have to learn Ruby too

* Rails is fast moving and has a lot of pieces

* the error messages can be cryptic and hard to decipher

I've been developing with Ruby and Rails for several years now and I still encounter cryptic error messages.

As a newbie I found it incredibly frustrating when Google did not bring up an immediate answer, it basically built a brick wall around me. I don't think this is Rails' fault per se, it's just the nature of the beast.
The nice thing about space mirrors is that of all the climate mitigation methods I've heard, they are by far the most controllable. Solutions like "let's stuff the oceans full of iron to grow plankton to absorb CO2", even assuming they work as intended, have the problem that they are irreversible. Space mirrors can put heat where we want it, and remove it from where we want it, and can do so on hours of notice. It's actually the least simplistic solution. It also actually allows some reasonable engineering experimentation with commensurate levels of commitment.

Unfortunately, it is also the easiest to turn into one hell of a weapon.

Then, following that logic, climate control in general is one hell of a weapon. If anybody actually can control the climate, can we allow them that power? Things like "turn it over to the UN" aren't a magical answer to that problem because "the UN" is ultimately just another group of people, not particularly imbued with magical resistance to the temptations of power. (Arguably, quite the opposite.)

But assuming the massive political problems can be solved, problems which all climate control schemes have equally, space mirrors are actually the one I favor most. Too many of the other ones have a failure case of "triggering an ice age", and for all the words spent on explaining how bad global warming is, ice ages are several orders of magnitude worse than the worst global warming story I've heard. A true ice age is the end of civilization.
It talks about the history of banking and the fractional reserve system, the difference between commercial and central bank money.

What most people don't realize is that banks don't have to actually have the money they lend out. That's the basis for our monetary system and while it has nice qualities, like spurring innovation, there are some undeniable drawbacks.
Linkbait title, but good post. He's right. Ideas only matter when moving beyond the idea phase. Too many people sit on a "big idea" waiting for some hidden force to propel them to action, while hackers find a way to get a prototype built.
All instructors (and everyone else, except front end staff) are paid per unit - industry wide.

Depending on aircraft it generally costs around $12-20 per seat in the plane. The equipment costs around $15k to buy new is fairly expensive to maintain. Instructors earn anywhere from $25-85 per jump, depending on facility, the weight of the student and whether or not the student bought a handcam video. Also, it generally costs about $10 to pack the parachute after the jump. So you're looking at around $60-120 in cost for each tandem jump.

Outside video (a videographer) costs 1 seat and pays around $40-70 to the videographer. It pays more because they have to buy their own parachute and camera helmet ($2k-3k and $1k-2 respectively). They also have to pack for themselves. They also do less work, so it's harder to keep them around.

The aircraft generally cost around $1 million to purchase, give or take a couple hundred grand (Otters, Porters and PACs). Smaller, less efficient aircraft are available for $35-50k (Cessna 182 and 206s). To lease an aircraft costs about $600-1000 per hour for a large one (like an Otter), $150-200 for a smaller one (like a Cessna), both prices including gas. You can get a flight up in about .2-.3 hours for the larger planes, .4-.5 for the smaller ones.

The larger planes will get 12-24 people in them, the smaller ones 4-6.

Q: How to do make a small fortune skydiving?
A: Start with a large one.
It drives pageviews?
Having started with Rails 3, I'd have to say that's not really true.
support uwsgi excelent!!!!
In this case, it is! The GP is using a uniform prior assigning "equally good chance" to either outcome (good or bad). http://en.wikipedia.org/wiki/Prior_probability

Of course stopping there seems to be silly since I'm sure more informed people have evidence that can shift that probability one way or the other.
There are exactly 5,000 comments on this blog post right now. It appears almost all commenters oppose the new design changes. It will be interesting to see whether Netflix will roll back their changes.
"sidestepping the obvious question of what we mean by improve"

This, by the way, is rather a massive problem with current discourse. Anyone who wants to talk about "damage" to Earth's environment ought to be required to specify their definition of "optimal". It turns out to be rather tricky, but without it a lot of this debate is politics, not science or engineering.
I don't know actual statistics, but I think that in every place there is something like a "normal temperature" each season.
Land was being mass produced in the first half the 17th century. My guess is that people couldn't imagine running out of land because you could keep reclaiming it from the sea, but they could imagine running out of tulip bulbs. Thus they undervalued land, and overvalued tulips.

Similarly, during the .com bubble, people couldn't imagine a slightly improved search engine would be worth anything, but an online grocery store seemed like a gold mine.
I've always thought this stuff was more important for your team, but then I realized that it's equally as (if not more) important for you as a founder. Kanter's Law is true, "everything can look like a failure in the middle". The little victories help you get through the middle.
A 10% performance penalty to get down and dirty with your Domain Model and go all HSQL isn't exactly a big price to pay.

Take a peek at Paul's benchmark. Iterate and instantiated 100K empty objects in 10s. That's crazy. You're talking about something that would probably take 1ms in c#. You're talking about a performance deficit four orders of magnitude large.

Regardless, I think you've entirely missed the point. The point is not that the O/RMs generate inefficient queries. They may not be perfection, but for what you're asking of it, by and large the queries are not the issue. We're talking about raw method-dispatch.

This simple benchmark takes about 600ms on my MacBook Air:

require 'benchmark'
puts Benchmark::measure {
i = 0
1_000_000.times { |x| i += x }
}

The same thing takes 1ms in Mono:

using System;
using System.Diagnostics;

namespace dispatch {
class MainClass	{
public static void Main (string[] args)	{
var s = new Stopwatch();
s.Start();

var x = 0;

for (int i = 0; i < 1000000; i++) {
x += i;
}

s.Stop();

Console.WriteLine(s.Elapsed.ToString());
}
}
}

(Forgive me, it's been a very long time since I wrote any c#, but this gave me an excuse to try out Mono. :-) )

You could argue that it's not exactly identical code, but it's fairly idiomatic I'd think for each language.

The point is, the sort of performance deficit you carry with Ruby has real consequences. You don't have to dig very deep at all until such concerns are no longer academic. There's financial applications I've worked on in c# doing transaction reporting with 1,000 rows or so per page that would simply put be at a severe handicap under Ruby and it has nothing to do with the RDBMS.

I'm certainly not gonna give Ruby up any time soon. But it's important as a developer to at least be aware of the shape of the box you live in I think.
Given that the point of this is to have fun and also tease out people worth hiring, having ambiguity in the problems is a good thing I think. Rarely is a real technical problem so clearly and obviously defined. So requiring a bit of thought and intuition might prove to be a good filter :)
This strategizing was done almost 100% on our end. We consulted with them and asked questions, asked for other skydiving facilities that ran Groupons, looked at them, called them and talked to them, etc.

We modified pretty much everything about our business around running the Groupons.

Still, I feel that our rep did a good job helping us out, much more so than another form of marketing would. Would you expect a billboard company to come to my business and tell me how to run my business more efficiently, make sure I can handle it?

We ran a radio promotion around the same time and they did ZERO insofar as making sure we'd be ok. It also cost us a lot of money.

Restaurants and coffee shops have more to overcome when running a Groupon, but that's their job, right? Pick a good marketing strategy, be successful, make good decisions, etc.