skysight-inc/HackerNews huggingface dataset:
Did you forget the link? :) http://iamtrask.github.io/2015/07/12/basic-python-network/
Are Strings really needed in java
Because deceleration takes time, unless you want to be flattened to the front of the vehicle. The more stops you have, the lower the overall speed will be at which this thing operates. High-speed trains in Germany that can drive up to 350 km/h often only average around 120 km/h over their total distance because with stops in between you spend a lot of time accelerating and decelerating. And where stops are more frequent you can't even reach the full speed since you have to start breaking already before you're done accelerating.

There's nothing inherent in physics that prevents self-driving cars, but unless you want to jump out of a moving hyperloop pod, it has to come to a stop and accelerate again; and it does so slowly enough not to kill its passengers.
Interesting exercise. I'd like to see the justification for the "3" on the right side of the equation though. Does anyone know where that came from or have a reference?

A lot of the estimates are really bad and completely ignore sensitivities due to assumptions, especially with CAC in the denominator which can have a massive effect when the range of ratios offered in the article is 0 < r < 3.

The difference between a LTV / CAC ratio of 2 and 3 is 50%. If CAC is assumed to be $3000 when the ratio is 2, then it only needs to drop by 33% to $2000 to get the ratio up to 3.

The author appears to consistently guess at CAC and then completely ignore the fact that a slight shift in the right direction would quickly put a company back in unicorn territory.
Happy to see people challenging the Hadoop stack. Wishing you success.
What's badly needed here is a sensitivity analysis.

For example, he lists ZocDoc's CAC as in the range $1k to $10k.

If it's $1k then their LTV/CAC = 4.8 (wow good!)

If it's $10k then their LTV/CAC = 0.48 (wow horrid!)

The author chose $3k, seemingly arbitrarily.

There's nothing wrong with arbitrary assumptions in general, but in this case a lot more scrutiny is needed before we judge if its a unicorn or donkey.
> The CEO can have very conflicting opinions and actions compared to the Board.

Which usually does not end well for the CEO.
5 Things Every Employee Should Ask Their CEO
You beat me to it by 60 seconds, but you made the point in a for more general way:-

The sensitivity of LTV/CAC to the assumed CAC is supremely important here.
I've been really happy with 500px. Their interface is quite pain-free to use. They're more geared towards photographers looking to host their portfolio
Reminds me of Croquet (a foss real-time 3d multiverse system similar to second life) and the TeaTime protocol/system:

http://dl.acm.org/citation.cfm?doid=1094855.1094861&preflayo... (sadly paywalled)

Essentialky if you model your world/simulation as objects and events/messages, and you can isolate input (user input, possibly clock ticks) - and you can order external inputs in a (distributed/consistent) log (a la apache kafka) - then you can have a simulation that runs in parallel and lock-step across many clients.
Subsidies are only needed to push a technology to market where it wouldn't be economically feasible in the beginning. At least in Germany the current state is that renewable energy is on par or cheaper than coal and nuclear, even without subsidies. In such cases it makes sense to cut the subsidies. Don't know whether that's the case in the UK already, though.
Numpy can basically be considered to be part of the standard library for Python so I'd say using it still qualifies as "using Python". Pandas is newer but is graduating to that level of ubiquity too.
This is terrible and it undermines The entire justice system. This is treason against the constitution.
The entire article appears in bold.
thanks for your valuable tl;dr.
if Seinfeld would have been a blog post in 2015, HN would summarize:
tl:dr nothing important, kinda funny, but I like Frasier
The diff between Haskell and Python is not functional programming, I program functionally in Python, it is the type system.

This is subjective, but having tried Elm with its Haskellish type system, it seems that the type system makes me think hard about things that ultimately don't matter much. It might depend on your problem, but I doubt it. Even doing numerical computation with Theano I find myself better off just executing subexpressions and seeing results and the shape of the tensors interactively is more useful than thinking really hard how the operations transform the shape.
Similar graphs for Denmark, covering the last 15 years. Daily records in 2015:

- Wind: http://apps.axibase.com/slider/energinet-2015/?slide=10

- Conventional: http://apps.axibase.com/slider/energinet-2015/?slide=11

Notice that you really have to have a) substantial spare installed capacity and 2) interconnects to survive a day without wind.
Mentioned briefly in the article, but worth repeating here: iFixit (who Patagonia used to publish the repair guides) is a remarkable company. Their ethos matches the article exactly, and aside from the (economical and awesomely useful) electronics repair kits they sell, they are also dedicated to building an open access wiki platform with rich support for repair guide resources.
Completely bizarre attitude (creator of pandas here).
This may be a liiiitle bit off-topic, but I really need to get it off my chest: Python for high-performance scientific computer works beautifully... it's a dream. Scipy/numpy, matplotlib, pandas, ipython. They're all unbelievably awesome. It all just works.

Except, when you're on Windows, and it just doesn't. Just installing things and doing the 'hello world' for aforementioned libraries is laughably impossible.

So, use Python, but use it only on Linux.

(Okay, if you absolutely must do it in Windows: Use Anaconda).
I don't disagree, but it's not because his wealth is actually valued at 45B that he deserves more democratic power than me or anyone else in the US or the world.

This trend for "corporations can make the world better" is misleading. Everyone else has failed: military corp, narco, public corp (as in ancient urrs), ... If only one has succeed, we should see it.
"Opinion: Blacks are corrupt. Maybe not all of them, but enough of them that "blacks are corrupt" is true. This will always be the case. Blacks don't fight crime, nor prevent it. They create it. If you think this isn't so you haven't had enough exposure to them. Maybe my opinion is coloured by my experience: they {put bad thing here}. If you see a black, cross the street."

Do you honestly think that this is a fair statement?
Next silicon valley........
Why not both? -HT
>I can't imagine how something like this, or Snowden's docs, could have leaked in the pre-internet days.

No imagination needed.

The Pentagon Papers, Deepthroat, Treaty of Guadalupe Hidalgo, the Hutchinson Letters, Mordechai Vanunu, and The Iran–Contra affair all predated the internet. Thats just off the top of my head.
Specter of Drones Firing Tear Gas on Crowds Worries Human Rights Group
Should You Start Using Contracts?
That's because a very large majority of developers are shit at security (and I'm a developer).
There are a lot of strategies for handling this. One of which is, accelerate the pods on a separate, shorter (semi-circular?) track before merging into the main "pod stream". Similarly, decelerate on a separate, shorter (semi-circular?) track. There was some prototype (or theory) of this discussed in a link on HN several months ago in which a Chinese train station accelerated (or decelerated, I forget) a car to match the speed of a passing train to append that car to the train as it went by.

Just because you need to accelerate and decelerate doesn't mean you need to do it on the same shared track as the main line.
I think a bad sentiment here is mostly generated not about what Mark says on his post, but what he does otherwise. We've seen a fair share of controversy regarding facebook, privacy practices etc, we've seen a fair share of controversy regarding internet.org.

I for one find it all skeptical - I don't see how his ideas would align with facebook goals as a company
This is nothing new to someone in India. We've always been this radical.. now and forever. =)
How do you know this? Trident and Presto were both closed source, did you do some contract work with both Microsoft and Opera at the time?
This is a good summary / refresher and worth a read, even if you're familiar with most of the productivity methodologies out there. I didn't know the Eisenhower Matrix had a specific name.

Not linked in the article (but worth a plug IMO) is the Mac app Vitamin-R [1]. I've started using it again lately and I'm finding it useful. It combines several of the methodologies in the article: Pomodoro, Time Boxing and Biological Prime Time. With the latter, after each pomodoro Vitamin-R asks whether you were in flow or felt distracted - over time it generates a graph of your peak productivity times & days of the week.

[1] http://www.publicspace.net/Vitamin-R/
> If Numpy, Pandas, etc. were wrappable from JavaScript

But they aren't, of course.

For science, the fact that so many great libraries are available and they all use Numpy arrays as base datatype (from image processing to GIS to machine learning etc etc) is a real strength of Python and I doubt another lanuage is going to achieve that any time soon.
Actually, Google was the one trying to sell itself to Excite. For $1,000,000. A board member talked the founders down to $750,000. CEO of Excite said no. It's now considered near the top of the list of worst decisions ever made by a CEO.
15 Podcasts for Everyone in Tech
Hello ktavera.
I sent my application last month (from the previous HN Hiring thread) but did not receive any feedback. Are you looking for senior developers? Thanks
Your first paragraph actually describes D. In the D world the compile time language and the runtime language is the same thing. You can take a look to see if you like it.
New integration tool in Azure marketplace
This is a severe distortion of what really happened. The co-designer of Civilization was https://en.wikipedia.org/wiki/Bruce_Shelley, who worked at Avalon Hill for six years before moving to MicroProse. The similarities were not coincidental. Civilization (the board game) was extremely successful and well-known, and is still influential on video games, being the origin of the "tech tree." https://en.wikipedia.org/wiki/Technology_tree
I agree with you about moralizing - it can be (and often is) harmful. But in this case the advice is sound. Taking care of your stuff, not discarding it just because it is a bit worn around the edges, and trying to repair it instead of just discarding + buying new; is there something wrong with this approach? not sure it is a "single best thing", but it would make a difference. A large one imho.
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AVAILABLE for onsite interview anywhere in SF Bay Area (at least) until December 9th, 2015.
Not disagreeing with you, but would you mind elaborating on that?
I have a hard time reading this graph:

http://lh3.googleusercontent.com/Dqp5VJzn4SRzlKiWcVdavOWhYIu...

I can see that on either side of the graduated tiles, the diagonally adjacent plots are mirrors of one another.

But the x/y dimensions on the quasi-random plots seem so distorted, that information is destroyed. The fact that none of the points are color-coded in any of those tiles, means I can't intuitively draw conclusions by noting corresponding dots across second and third tier composites.

each time we pick a point, we should pick it
as far away as possible from every other point
across all dimensions

I don't understand how you can assign a plot like that, and still constrain the mass (M0) and initial helium (Y0) points to the graduated markings on their respective tiles, and come up with a diamond-shaped quasi-random pattern, which still communicates the accurate mass/helium relationship for each dot?

Why is the upper right corner in those two M0/Y0 composites sparse, but there are still diamond grid clusters across the rest of those particular tiles?
Way to go todois ;-)
The Sinclair Spectrum port of Elite did something like this in the tape loader where, while loading off an audio cassette, it would load a new tape loader code and jump into that, and the load a bit more of the game, before grabbing yet another loader, and so on; it was a pretty effective way of stopping people getting to the game code without extra hardware.
Saying we consider time reversibility true for more or less philosophical reasons seems a bit of an understatement to me. Conserved quantities prevent states differing in at least one conserved quantity from ever evolving into the same state, i.e. conserved quantities partition the phase space and states cannot cross those partition boundaries. This also has to hold for all isolated subsystems. And conserved quantities arise from symmetries like homogeneity and isotropy of space which are pretty solid empirical and experimental facts. It's all interlinked and I imagine it would not be to easy to eliminate time reversibility from the laws of physics without causing some odd consequences.
> Make 30% on investments, give away 10%

Any profits made from investments go back into the charity's holdings. This is a good thing.
Nope, more recent than that. Yahoo Screen, including the sixth season of Community.
Honestly, I used to trust Google a lot. Then things like the NSA leaks happen, and other questionable Google changes, and I'm sorry, but I lost that trust. I use as little closed-source stuff as possible now.

I'm sure it is frustrating, but you'd have to thank the people in charge for that distrust. I wasn't born with it, the cloud-providers earned it. I used to think this was tin-hat territory myself.

IMO, the solution is to stop storing things in the cloud, and start giving me the tools to do it myself. I have no idea how to work that out financially. If google made a "maps app" that was open-source and I could run on my own server, but charged for it, I would probably buy that because I like the service so much. But as it stands, I try to avoid using it as much as possible, because I simply can't trust Google.

EDIT: Forgot to answer this

> if the primary effect of the conspiracy theorists is to throw bricks at the people who are trying really hard to make sure the bad things never happen, then which side are the conspiracy theorists really on?

At the end of the day, Google just doesn't do enough to make me think that they are "making sure the bad things never happen". I'm sure there are a lot of people who are trying hard to make that true, but how can I know that is true for everyone? What can you offer me other than root access to your servers? I'd honestly like a good answer to this, because I just don't have one.

And the amount of data/power that Google has is just too much for me to think that they won't "get greedy" some day. If up until today, Google was a good company and wasn't abusing anything in any way, and suddenly tomorrow they turned evil, why would they erase my data first? They still have it, and I have no control over whether or not Tomorrow-Google will keep it.

> ...then which side are the conspiracy theorists really on?

The side of trying to validate whether or not things are as they say on face-value. Whether thats Google's side or not is up to them.
also old: https://signalvnoise.com/posts/1941-press-release-37signals-...
Hide Calls and Texts from Specific People on Android Device
Sadly, I doubt that manufacturers are consciously thinking about durability and (more-so) repairability when planning.

"In some cases repair is the most efficient choice but in others it is not." I doubt that choice - one way or another -is being made very often.

If a tradeoff has been made, then it would be great to have that knowledge as a consumer and thus be able to make an informed decision.
Amazing Story of This Young Man Shows Why Professionalism Matters in Business
I would not be surprised if that is truly the most effective behavior change for a group of people to execute on.

I'm sure that individuals among us may be in a position to help our planet in a more effective manner, but the old saying "reduce, reuse, recycle" is in that order for a reason.

I'm sure this campaign brings a ton of branding benefit to Patagonia, but I certainly can't dismiss it as a cynical ploy to take a hypocritical moral stand. It takes a fair bit of courage to take out a huge ad on Black Friday and say "our company's products damage the earth. Here are the numbers. Please don't buy them unless you need to." The world would be a better place if more companies were willing to be that forthright.

In any event, they are literally publishing numbers about the impact of their manufacturing process. So it should be straightforward to determine how optimal her strategy is.

(Incidentally, I'd love to see those sorts of numbers across more industries. For example: should I keep driving my 9-year-old gas car, or should I incur the environmental impact of battery manufacture etc. for a new hybrid or all-electric? If the former, then at what point should I ditch my current car, given how many miles I drive annually?)
While some companies, like Ricoh, DeWalt, Caterpillar and Lenovo have made
repair and remanufacturing a staple of their business model,

This is why I continue to buy Lenovo, even though it can be argued that overall quality and durability of a Thinkpad isn't what it used to be when IBM still owned the brand. When I buy a Thinkpad (like the T440s I bought last year), I am reasonably assured that if something breaks, I can take it apart by myself and replace or repair the individual broken component, rather than having to throw out the whole laptop and buy a new one. Lenovo publishes the bill-of-materials for its laptops online, as well as the repair manual, which makes things a lot easier when trying to match parts. Just this weekend, I "repaired" my laptop's inability to receive 5Ghz wifi signals by replacing the stock 802.11 b/g/n wireless card with a 802.11 ac part. If this had been a Mac or an ultrabook, I would have just had to deal with the limitations of the hardware as it was.
I think the only game changing thing about the hyperloop is that it is getting rich people excited about public transit. I mean, my guess is that we're never going to get a SF <-> LA transit path that is faster than a airline with a "skip the security" pass; I don't believe that the hyperloop as envisioned will never be built.

I know that sounds trivial... but it's not. Public transit is a failure in America in large part because wealthy people, even wealthy people who support public transit in general, don't want public transit near them.
Hi plusquamperfekt.

I don't know your mail address or telephone number. If this message manages to reach you - can you explain your point a bit more?

If the private key would _be_ the identify, that'd be awesome. And maybe I fail to understand ChatSecure/Signal. I'd be glad to be corrected. But as far as I understand, that system ties a user to a mobile number, because 'that is as good a unique identifier as we get' and uses that instead. I think Threema does what you describe - or at least expects you to exchange keys via QR code when you physically meet?

My gripe with telephone numbers is this: I don't want to be tied to an identity I cannot control, to an identify that is public knowledge and unchangeable. I want to contact people via IM without them being able to call me.

Phone numbers are for calls (okay, texts for historical reasons).
Schelling Points, Prediction Markets, and Consensus 30 November 2015
I don't think 'internet.org' is the best way to teach the lowly users how to best spend their money.

The responsability of teaching should be public (so like a government), not just 3 random guys.

Zuck also says "you need to work in a hangar"... Nah, I want my workplace to be better than my home.
The major implementations of the JVM are jited, not interpreted. Yes, you get great performance with jitting, tho not necessarily without unpredictable GC pauses and without a loss of energy efficiency from having to run a jit alongside your actual code.
Raspberry Pi Zero, or Minus One?
Blocking a single molecule defeats chronic fear
A Handy List of Productivity Software to Help Your Company Work Better Today
You have changed 'individual consumers' to individual.

As a consumer, make the choice to consume goods that cause less harm and then make them last longer. As an individual, there are likely better things you can do, sure.
Claiming that using wrapped libraries written in another programming language (LAPACK, anyone?) is an inauthentic usage of the language (here, Python) is pedantic and unhelpful. C is just a wrapper for assembly, then, right?
It is interesting that the same rich people created a political system that allows the public to be so disengaged.

We need the 99% tax because we had it before, and at that time, the public was more engaged. It will take time, but people can learn civic skills.
Third Way Tries to Revive Nuclear
The Evolution of Stomach Acidity and Its Relevance to the Human Microbiome
Too bad I can't think of anywhere within 300mi that is both (a) large enough to justify a hyperloop stop and (b) isn't an awful hellhole (Fresno). Maybe east of Sacramento?
Terminology is important. A BST is what I defined. A balanced BST has an extra property, but you don't get to call a balanced BST just a BST, it only adds to confusion and unclear communication.
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Religious flamewars are not welcome on Hacker News. Please do not conduct them here.
I understand your sentiment, but I would hesitate just a moment to judge it so quickly.

It's hard to look at this sort of statement, especially when it's posted on Facebook. The source of 'Like this posts to do XYZ' or '#KonyIsABadGuy'. But really, the ideals that they strive for seem to build on those that have formed the foundation of our very society. The equality and advancement of mankind. In many ways, this seems no different than what Jefferson or Franklin had in mind.