skysight-inc/HackerNews huggingface dataset:
Except it's not random who applies for the lottery. And also charter schools are notorious for rejecting students for various reasons that public schools are not allowed to use, including rejecting special ed students, all in the name of making their test scores look better: http://nepc.colorado.edu/newsletter/2013/05/tcr-dirty-dozen
are they charging $5 per device connected to the RPi, or per RPi? Is it monthly? Website is not clear at all.
When Glenn Greenwald Meet Edward Snowden
Great post. Superb introduction to the concepts with helpful illustrations. Adding a few ideas to the mix...

Typically a mature SaaS business has about 50% of its revenue from new customers and 50% from renewals. Early on that number is skewed to growth but if a company doesn't invest in retention early on, the company can go upside down, fast. Watching cohorts each month as their subscription expires is a good way to catch this early. Especially if you're in accrual accounting, because you can't recognize new revenue right away.

The 3x CAC for LTV is a good rule of thumb but does require you think about what LTV is. In the late 90s companies acquired customers using a 5 year LTV assumption which led to some really inflated valuations and lopsided businesses. I am conservative in my own startup right now, no more than 1-2 year LTV assumption for now to preserve cash flow until product market fit and retention are more consistent. one great reason for taking investment is to take some risks in acquisition on LTV, Gambling intelligently that you can improve your retention enough to match.

Early on, the ratio is likely to be even higher until you can drive the inefficiencies out of the spend. And as cost per click goes up in a given market you have to think very, very hard about it. If you're in an enterprise SaaS business, especially in marketing, it's really ugly for top of funnel terms. I've seen some terms at $11-$12 a click.
#selfie spanish official version #yometomounselfie by the chainsmokers n WilJ
It's OK, there should be some relatives around to make a restorative payment of camels or wives. Unless they're from a particularly powerful clan, in which case they may be able to avoid paying the Diya even if they can't swing the outcome of the case.

Personally I find it quite odd that so many self-proclaimed libertarians are so favourably disposed towards what is essentially a system for punishing the collective for the actions of the individual.
I prefer libraries. I'm partial to jQuery[1] for DOM manipulation, simple effects, and AJAX. I love Underscore. Both libraries allow me to pick and choose which parts of them I can use without imposing on me to do it The $FrameworkName Way. That said, when I can use pure JS I do.

Lastly, what are your thoughts on code maintenance? I feel like there is something to be said for "Get it done" thinking and "Make it maintainable", and sometimes they don't see eye-to-eye.

You're right, they don't always see eye-to-eye. Frameworks are handy if you need to "get it done". You also need to educate your customer that you will have to make trade-offs and cut corners when trying to just "get it done". But I also argue that with enough experience you can, in fact, get it done and make it maintainable. I've seen that time and again.

The reason I don't believe you can write something cleanly with a framework and it be easier to maintain is that the framework is a black box of unknowns. So one option, as someone else has mentioned, is to try to fully understand that black box. But then you've just tied yourself to that framework. Wouldn't you be better served mastering the technology that the framework is written in?

1: jQuery proper. jQueryUI isn't too bad but is still a little more black box than I prefer. I really dislike jQuery Mobile for all the reasons I dislike frameworks.
Fuel cell vehicles have never made any sense. It's still being turned into electricity anyway, so it's still an electric vehicle. There happens to already be a distribution infrastructure for electricity almost everywhere. The same can't be said for hydrogen.

According to the US Department of Energy, there are eleven public hydrogen stations in the US, almost all in Los Angeles. There are more compressed natural gas stations in my state alone.
Kinect-less Xbox One is finally on the way this June
What It's Like To Own A Tesla Model S
I haven't "mastered" React by any measure, but I've been using Angular for quite some time, and I find that apps written with it become really frustrating to maintain after a certain amount of complexity. I see Angular somewhat akin to C++ in that it's the most powerful and flexible (IMO) of the popular JS frameworks, but you're also going to spend a hell of a lot of time creating your own structure and conventions. This is a fine tradeoff if you need the flexibility, but for my use cases, React is much simpler and less headache-inducing to use. I just find that I can fit React's model into my head, whereas with Angular I'm constantly needing to figure out how to translate my mental model of my app into code that actually works, and dealing with weird, undocumented edge cases.
It is your data - Facebook, Google etc are just custodians of your data and you have the right (under EU law) to have that data removed or anonymized.

The legal requirement is for the information to be published (once) and then, in the normal course of events "forgotten" after a period of time.

It is not the publication that is a concern, it is the permanence of it, and the ease of access that the ruling deals with.
I haven't gone door to door and done a proper survey if that's what you mean. But yeah, I've met people who either have avoided getting a job or lament not having one despite spending most of their time watching TV all day.

>things like public assistance benefits were set up in a way which penalizes anyone who gets a job.

So true. However, in many cultures pride is more important than the monetary benefit of free loading.
Transform Your Skills: Simple Steps to Set Up SQL on Hadoop
How to Tell If Your Friend Is Faking a Laugh
The ad industry is like a brand trying to remain relevant by chasing new fads.
great add and summary. Hadn't seen this.

On your point 5--amen. If marketing is using affiliates, you see the same problem, plus issues of fake sign ups. Have to make sure affiliates are compensated only on 90 day + signups.
Niche ebooks seems the most common way I've seen to generates a little extra beer money (or more) from a development blog.
Poll HN: What's your mobile?
Which phone(s) do you own?
Do you like it? Why?
Is it practical (does the battery last?)
What will you buy next?
Microsoft disabled RC4 in latest .NET update
Ask HN:  Lisp, Haskell, and the Blub Paradox
Lisp is the classic "top of the power curve" language for the Blub Paradox. Lisp people look down on basically every other language, and ask "How can you get anything done in those languages? They don't even have macros." (That's Lisp macros, not C-style macros, which are a much different thing.)

But Haskell programmers look down on Lisp (and everything else), and ask "How can you get anything done in those languages? They don't even have a decent type system." (And no, C/C++/Java types are not what a Haskell programmer calls "decent".)

It seems, then, that we have two different languages, each looking down on the other, and sure that it knows why it is looking down, that is, sure that it knows why the other is less powerful.

My question: Is the Blub Paradox wrong?

The Blub Paradox assumes that all languages can be ranked on a one-dimensional axis labeled "power". But power is the power to do something. What if the "something" determines (at least to some degree) what "power" looks like? Maybe a better view is that programming languages look like a tree, and your problem looks like a vector. Pick the language that gets you the furthest in the direction of your problem vector. (This view means that you cannot meaningfully compare the power of different languages without specifying the problem domain, unless the languages are on the same branch of the tree.)

Here's an even stranger question: Is it possible that Haskell's type system and Lisp macros are doing somewhat equivalent things?

Responsible, thoughtful answers are welcome. Flames are firmly discouraged.
That's the same type of generalization the OP wanted to avoid.
It's also not either-or. If you have components written in Polymer that you want to reuse, in principle, a React-like framework could render them. (I don't know how well this works today.)
Note that there is a 'transport' checkbox that we can all enable to see where you've gone over the past year.
> While its core offering is basic — it collects money from members and pays for their care when they need it...

Right, so you just described the concept of 'health insurance', any/all health insurance. Which is not necessarily 'basic' at all in practice. What was the author trying to say here exactly?
Those are fair enough reasons. I see being tied (permanently) to a provider like Cloudflare or AWS as a problem. I'd rather use the www and be allowed to move to providers that don't necessarily offer the same features, or to my own infrastructure where that is or is not an option.

Let's agree that for the most part it's a bad idea to change from www to naked or the other way around after the launch of a website (for seo reasons). So you have to pick one at launch and try to stick with it. Why choose the option that looks nicer but has problems associated with it and potential vendors not supporting it, vs the one that arguably looks messy but that all users everywhere are well accustomed to and has none of the configuration issues that affect naked domains?

There's postmortems out there about using naked domains and DDoS attacks. There's issues with load balancing, with domain configuration, with cookies.

If your website gets overrun by HNers, what's your plan to compensate quickly? How much of your plan is bogged down by the fact that you're on a naked domain?
Here's my counter anecdote:

I also work at an institution that can be described like yours. To me, listening to a professor lecturing has always been the most effective way of learning something. Not because the lecturing quality was so outstanding but because I apparently can absorb new information better when somebody explains it while I think along. I fall asleep much quicker when I read a text book (as opposed to a lot of other students).
Yes, it is tricky to compile without typed arrays. It means we need to disable LLVM optimizations, and also a lot more undefined behavior in C will fail (anything that assumes memory aliasing).

With a little effort stuff can be ported, I ported CPython that way. But typed arrays is far better.
Thanks for the head's up. Just updated my github page to redirect to www and I can see a massive improvement.
adapting a quote from Office Space, every RFC shall ask, "Is this good for the internet?"
Actually, seeing this post and also that I ve struggled in finding those resources, I have created a github repo yesterday which can be used by the repo owners to post the contribution required and the contributors can take a look at it..

https://github.com/avinoth/OpenSourceForBeginners

only problem, don't know what to do next.. let me know what i could do next..
In many places you can't get rid of the bad teachers - largely because of overly powerful unions. People who would make good teachers are driven away from teaching by the perverse incentives. Yes, the number of good teachers is finite, but so few of them are actually in front of students that the upper limit hardly matters for the foreseeable future.
How Median Will Make Your Business Better Than Average
An ode to 17 databases
I think the real question to me is about how much energy can be stored in a fuel cell vs the current available batteries.
The result of thousands of years of meeting the local maxima.
I would argue that high school education is generally better in Maryland and Virginia, where school districts are by county (or equivalent city) than in Pennsylvania, where there are many more school districts.
Bitcoin disrupts gaming, how to get downloads for only $0.50 in bitcon
This is really cool and shows how bitcoin is ready to disrupt gaming. Score 50 points in this game and you'll get $0.50 in bitcoin.
This is awesome for both game developers and gamers
https://gamerholic.com
I would love to hear what the tipping point was for fuel cells. I suspect Toyota doesn't believe that battery technology will get the point that recharging gets close to normal gas station stops where hydrogen might.

Last I heard Hydrogen was still problematic in winter cold just like batteries.
"a) A small core API instead of a sprawling standard class library"

Using adjectives to accentuate, does not an argument make. "small/core" and "sprawling" all have loaded meanings. And if you wish to convert anyone but the already-converted sub-culture inhabitants, you should probably quantify what you mean and why it's a benefit.
It's definitely a lot to take on. I'd probably start with just plain Clojure to learn the syntax and how to do functional programming, then look into ClojureScript.

Get comfortable using Lein and editing your project.clj, then check out this plugin:

https://github.com/emezeske/lein-cljsbuild

It's a big investment but learning Lisp will repay you. There's tons of classic CS literature that you'll now be able to unlock and immutability really is the future, so it's good to start getting acquainted with it.
I would be curious to compare this PostgreSQL + RabbitMQ + Redis solution with Cassandra. It is very well suited to time series data which is why it is so popular in advertising industries.

Also you would think that rate limiting would be handled at the load balancing layer with Nginx, Apache, Layer7 etc. Way before it gets close to your app.

Not criticising Sentry for doing things a bit different. Redis is a fantastic technology.
I am pretty sure lectures will exist well after Sal and John will not.
It is so sad to see so many people failing to grasp what teaching is.
Most likely on an Apple TV you will often not just sit in front of it and watch it. Just like on an iPhone you don't just use it for phone calls.

It's pretty obvious the Apple TV will have a rich ecosystem of apps, many of which will do more than just stream media to the screen. With a good way to interact with it suddenly you have the most vivid, largest display in your house suddenly becoming much more functional. I'd imagine it will be more like a console in its capabilities but with the developer accessibility of the iPhone, iPad, etc, and with a much better physical interface than a controller or wand. As I said, an altogether different experience that has very little to do with the contemporary "TV" that we have now.
It's unfortunate that Scratch is built upon the Flash platform. Though Scratch has been released under the GPL, it requires nonfree software in order to run. Scratch looks interesting, but I cannot recommend its use until this problem is fixed.
I know. There are named places too, although not many.
Yep! Redis tends to be more for reading inflight rate/plan limiting, something I've not heard a lot about in conjunction with graphite (though it might be great!). We might bring back statsd/graphite for alerting/monitoring in general though, we've been looking for solutions there.
Fair enough. :)

I suppose I just think its neat and a production-ready version would be nice.
We're currently charging $5 device per month that you've registered through the RPi. The first two devices are free.

Granted, we're still getting a feel for what our pricing structure should be, do you have any feedback about our pricing structure currently?
Most professionals -- which teachers desire to be treated like -- have done quite well over the past 34 years despite fewer and fewer organizational defenses of their conditions. Unskilled labor is another story.

Unless teachers should be treated and protected like factory workers. Usually teachers object to that characterization, but if you want to argue for it, okay.

[1] http://en.wikipedia.org/wiki/List_of_professions

[2] I'm assuming you are using Reagan's election as the start date of the professional malaise. Call it a lucky guess.
Ask HN: Favorite payment processor (2014)?
As of now, May 2014 - What is your favorite payment processor and more developer friendly?
Yeah, releasing parts of Crowsnest as FOSS is a hotly debated topic internally. We would certainly be interested to talk to anyone who has experience running a business with a core product that is open source, especially if they were able to raise capital.
Great article! A few comments:

> In the perpetual license model, in-house IT staff managed all software instances and thus could incur the internal costs to switch vendors if they so chose.

This argument is flawed. There are switching costs no matter if it's SaaS or on-premise. This is why big companies outsource IT - it's easy to get rid of 100x Accenture consultants who specialize in SAP and replace them with 100x Accenture consultants who specialize in SalesForce. The switching costs are normally around process change, change management and training.

> Budgets are much more decentralized now, because departments often adopt SaaS technologies and make purchasing decisions independent of the centralized IT organization. In the past, the tops-down technology sales model made it very easy for a CIO to unilaterally replace application vendors.

Which makes them less sticky. Team frustrated using the $150/month PM tool that they chose? Good, they can get rid of it. LTV goes to zero.

> This is why many SaaS companies today invest aggressively in sales and marketing when adoption is high, even though it puts pressure on current profitability.

SAP and Oracle did too at one point. They're milking their ~90% gross margins on support contracts today. BUT, they still spend a shitload on cost of sale. I don't see cost of sale going down[1].

> As a general rule if LTV is 3X or greater than CAC, that’s a good sign that the business model is working.

The fundamental problem today with SaaS is that I have yet to see to that a scalable and sustainable LTV exists (i.e. "winner take all"). As the OP points out, we can insinuate (not completely prove) a 3x LTV for Workday, but what exactly are they doing that SalesForce hasn't done in the last 15 years? Lastly, if this is a winner-take all situation, then shouldn't we stop talking about SaaS, since "SaaS" = "Workday"? Or perhaps, is this simply pointing out that if you're a SaaS your sole position should be to spend donkey-loads of money on marketing/sales, because you'll just end up getting acquired for your customers anyway?

[1] - http://www.techdisruptive.com/2012/11/28/how-are-we-going-to...
"Fuel cell vehicles have never made any sense."

They have in the sense that I go to a station and fill up then leave in a reasonable amount of time. I don't have to alter my driving habits from the last 50+ years.
> in the same sentence as Saudi Arabia, where they sentenced a woman to flogging because she dared to drive

And in Iran women get executed for things outside their control[1]. How does your point relate to anything? Both Saudi and Iranian cultures have problems. What you mentioned is completely irrelevant. FYI, Saudi Arabia has colleges for women, where 100% of the student body is female (engineering majors too).

[1] http://www.nydailynews.com/news/world/iranian-rape-victim-fa...
Finding the right co-founder as a female entrepreneur
Well written software should generally be able to double as documentation.
Here is old one:

https://news.ycombinator.com/item?id=2444709
Turnspit Dogs: The Rise And Fall Of The Vernepator Cur
Man vs. motor
I never really got the "massive lecture size" thing. My university had ~20,000 students (about 15,000 undergrad), which I thought was mid-range as far as American universities go, but I never had a lecture with more than about 100 people in it. As far as I know, there weren't lectures that large anywhere in the university; I can only think of one hall large enough to accommodate lectures that large. It was used for administering tests for classes that had several hundred students (but all of those classes were split into several different lectures, often with separate instructors who worked together on the class.)

Is the massive lectures thing predominantly a state school phenomenon? Maybe my university being real-estate bound had something to do with it.

To be honest, I preferred large lectures and suspect I would prefer massive lectures for the same reason: smaller lectures are more prone to inane interruptions from students (typically students that had been skipping lectures).
I disagree. In my experience, the lectures are one of the primary reasons for attending a university. For a lecture to be effective, the students will need to have read the material that the lecture is taking on. Then, during the lecture, they should see why they have read what they have and understand why it is important, what the general implications are and so on.

For me, at least, a good lecture always brings together the assigned reading material in a way that I cannot achieve alone. A good lecture makes things click. Solving a thousand problems may also make concepts click, but a good lecturer will reduce the time needed.

TL;DR: The point of a lecture is not to tell you everything, but to bring together the material that you have already consumed and provide a different perspective than the book you read.
Writing an Orchestrate REST Client
The RAV4 ev is a pure compliance car. It's only sold in California, it's a 3rd party drivetrain and battery bolted onto the frame for a gas guzzler SUV.

So of course it's a terrible product. The only thing it excels at is getting Toyota enough ZEV credits. They recently changed the credit scheme, so now Toyota is switching to that:

http://insideevs.com/carb-zev-program-changes-tesla-takes-la...
Ok, so you could do

CAC = (quarterly business expenses [like salaries, rent, health insurance]) / number of customers acquired in that quarter

?
Split-screen iPad multitasking in iOS 8
Direct link: http://www.perfectaudience.com/connect

We're really excited about this new feature. Retargeting is great and for most companies it's the best performing marketing channel they have, but retargeting only reaches people you've already interacted with. How can you reach NEW prospects with the same ROI?

We thought a lot about the problem and are testing a P2P approach. About 100 companies, a mix of SaaS and retail are testing it now, sending connection requests and retargeting eachother's audiences. ROI has been fantastic.

If any HNers with audiences looking to connect with other audiences want to reach out (A4A), ping us at hello@perfectaudience.com and we can set you up with some extra free credits.
i think you need it on to take advantage of many of google now's features
A Masters in Education is, literally, an "advanced degree" by every definition I've ever seen. Ignoring definitions, the point is that it's expensive in both direct and opportunity costs relative to its future earning potential - most earners of masters degrees can expect to enter fields with significantly higher salaries, especially later in their careers.
I played with Scratch for some time with my 9 year old son. They've done an excellent job with it. We ended up using Construct 2, only because they've done an even better job and it releases to HTML 5, is playable on all kinds of devices including iPad.
Still don't know why users had to subscribe for Xbox gold to use free app at the first place. Now it's too late!!!
You should try reading his link.
i know there is google's location history but I want to do it storing the data locally on my android phone, and recommendations. I have it half assed right now with tasker
Ford Maddox Ford's novel The Good Soldier once a twice mentions as a blacksmith's saying "By hammer and hand all art doth stand" which is in the same spirit, and suggests to me that variants have been around for a long time.