skysight-inc/HackerNews huggingface dataset:
Very cool! I'm reading through "Seven Concurrency Models in Seven Weeks" by Paul Butcher at the moment, which discusses different types of concurrency models.

If I might try to elucidate what Butcher explained, the Actor model used by Erlang/Elixir was supposed to be a "purer" object-oriented programming model that defined how objects passed information between each other rather than the state and attributes of an object, and it worked well concurrently because objects don't share state outside of messages. However, actors are expensive because they tightly couple an object (the transport object) with a process (the mode of communication) unnecessarily.

CSP improves on this model by decoupling objects and processes. It eliminates the need for a process and defines a "routine" instead as a state machine for an imperative code segment, and in doing so creates a one-to-many relationship between a given routine and the hardware-defined threadpool. Buffer objects on a given routine and only exlicitly block when you need to. When an imperative segment of code is blocked in a routine, the routine relinquishes control of the underlying thread while managing state, and when it is unblocked, can begin executing on perhaps another thread with the given state. So it's easier to make imperative code concurrent. State machines are also much cheaper to create than an actual process. CSP is highly effective running concurrent tasks that may have lots of blocking events, such as tasks issued through network, which may be why a lot of the newer network-centric libraries like Kubernetes are written in a CSP-first language like Golang.

I'd definitely buy the book, I've learned a lot (never understood why Golang was so popular until now): https://pragprog.com/book/pb7con/seven-concurrency-models-in...
I don't actually know this to be 100% true, I base this off the fact that my iphone (and android) still has plenty of reception in my microwave but is entirely cut off when in my freezer. This behavior could be inconsistent across microwaves and freezers and blocking radio communication may not be a suitable proxy for blocking a CME that would be many orders of magnitude more powerful.
"Upon his release, (Collins-Rector) was extradited to the United States and ultimately pleaded guilty to nine (counts) of transporting a minor across state lines for the purpose of sex. He was sentenced to time served in Spain plus three years of court supervision..."

Well, that oughta teach 'im.
>Facebook has your phone number; well, do they have a new 2nd-factor token that makes the phone number useless without the token?

Useless? They already used it to infer my social graph by correlating it with my friends' contact lists. They don't really care if now there's a new token needed to actually call me.

I guess I'm saying that we can patch our problems with ID and authorization, like you're suggesting, but privacy harms go way beyond just that.
I remember a story about new ice age, where all heat was used by domestic heat pumps. The author failed to notice that you can fight against that particular climate change by using more refrigerators.
> but if banks are forced to make loans at a loss, aren't we effectively subsidizing people that don't repay loans? you might think this is a noble goal, but I'd doubt many people will be on board.

Perhaps, but I have little sympathy for the feelings of the better-off people who want to clutch every penny to the point that they are jealous of the help the needy might get. If they're able to block reforms, then I think efforts need to be made to change their attitudes.
I used to think it wasn't nefarious unless your gameplay mechanics essentially coerce you to pay for in-game currency to progress or otherwise fully enjoy the game. But it seems like it's enough just to sell cosmetic enhancements, because kids will be just as caught up in that as they would be in actual gameplay progression.

All that said. It's your kid, your card and your money. Kids a mischievous, but the blame isn't entirely on games companies.
I live in NYC and only ever take cabs when I am with a group that insists on it. I have no problem whatsoever with walking, cycling, or waiting a little longer for a train. And at all times of day.

It really is just a matter of shifting your expectation. Waiting for a train with friends late at night can even be a really fun experience that you can share with the other groups of tipsy people that are on their way somewhere. You might even meet someone new and special. To me, this is what city life should be, rather than the isolation of swiping on your phone in your ride-share.
Ask HN: How to learn trading of options, commodities etc as a data scientist?
As the title suggests. I am a data scientist interested in doing some amateur trading. Although i understand finance at a high level decently i am not sure if i can translate my R/Python and data skills to be an effective trader.

Is there an open course roadmap that can help.

Besides, is it even possible to make some money as an individual trader not working on the street ?

Would love to learn the opinions of someone in the field.
The easiest is to sell more to people who are already your customers. That's the main target. Occasionally you also want to try to conquer new people, perhaps from your competitors. Those are the two targets, out of which the first one is more important.
Couldn't pay medical bill on last day of the month, cause eom reports lock it up
https://medium.com/@joshdance/medical-billing-systems-problems-and-collection-agency-fun-bd229399e4e1

Is this a common thing? Seems like they need to mirror or externalize their reporting system so they can still use it as they are running reports.

Relevant bit:
"I went to the website, confidently filled out a bunch more forms and hit pay. Error. ‘This practice does not accept home payments at this time.’

Which is funny because the clinic told me to pay online. So I called them back. Again.

Turns out, I had tried to pay on the last day of the month, in the middle of the day. And what do they do on the last day of the month in the middle of the day? They run their end of month report. Which takes about 3 hours and completely locks up their system. So I couldn’t pay online until that report finished.

I patiently waited 3 hours and tried again."
From your cite:
"As a consequence, income inequality and investment are inversely related."

And yet, investment in America has never been higher. Prosperity is up, unemployment is at very low levels, employment of minorities is at record levels.

As for the Electoral College system, that's been around since the US was founded. We've always had a republic. It's irrelevant, anyway, since rich people don't have any more votes than poor people. There was little to no evidence of voter fraud in the last election.
Related discussion from today: https://news.ycombinator.com/item?id=19001530
Sharon's Leaving (in light of the layoffs) (humor)
"They also found that the kids weren’t aware of what they were doing. “It doesn’t necessarily look like ‘real’ money to a minor,”

Seems a way to create the best consumer ever: someone who gets the benefits while having no connection with the costs.
It may seem stretched, but I see some parallels with military drone pilots.
The time-traveling and live editing features make this incredible.

When I get the time I’d love to replicate this in Go (since I’m trying to learn Go at the moment). Nice work!
Why Isn’t X a Hook?
Google is in a great position here-- if the EFF gets everything they want in terms of privacy, Google can still show ads relevant to my current search query without remembering my search history.

But what would they suggest Facebook do instead of tracking? What ads are they supposed to show me if they're not allowed to remember things about me? There's nothing analogous to "outdoor gear in a nature magazine" that they could do instead.

I just looked through my Facebook Ad Preferences as the article suggested, and there's nothing there that would shock me. Yes, they know that I have an older model iPhone because I've used it to access their website. They know I'm a frequent traveler because they remember what IPs I've accessed their website from. They know that I'm recently married, and which zip code I live in because I told them those things. Using my zip code and some public records that anyone could Google, they can make a good guess about my race and income level. None of this is very scary because they only know what my friends and I told them about me. They can't read my email or listen to my phone calls.

Speaking of which, does anyone remember Edward Snowden? Remember when we were (rightfully) angry about NSA surveillance, the thing that does read your email and listen to your phone calls whether you consent or not, and the thing that you can't opt out of by deleting an app on your phone? They never stopped spying on us when the outrage machine moved on, and all this Facebook stuff seems petty by comparison.
I vet all of my kid's games, but this particular pattern was not a deal-breaker for me. However, I've set my Google Play Store to require a password for each purchase. When my kid gets confused, he gets negative feedback in the form of a frustrating dead-end. Hopefully that'll help learning.
https://news.ycombinator.com/item?id=18994760
> Sorry you got downvoted.

It comes with the territory. I rarely post popular opinions or popular facts. In this case I posted unpopular facts :-)
> I prefer untargeted ads since I'm not about to improve my knowledge or shopping performance just by viewing ads.

maybe this is true for you personally, but I don't think it holds in general. most of the time ads are completely useless (and I personally run ad blockers on every device I control) but every once in a while I see an ad for something useful I just wasn't aware of.

for example, I recently saw an ad for an electric hot plate that can keep a mug of coffee warm indefinitely. at first I thought it looked like a piece of trash, but then I thought what the hell, it's $10 and my coffee often gets cold before I finish drinking it. it turns out that piece of trash keeps coffee at pretty much the ideal temperature for drinking. I have gotten well over $10 worth of enjoyment from the thing and I would never have thought to purchase it if I hadn't seen the ad.
The breakdown is here: http://www.pewinternet.org/2019/01/16/facebook-algorithms-an...

13% "Very accurately"

46% "Somewhat accurately"

22% "Not very accurately"

5% "Not at all accurately"

(and 3% Refused, 11% Not assigned categories)
>But what would they suggest Facebook do instead of tracking?

Why do they need to care whether Facebook is successful?
I still use this technique.
Calendly also works this way. I guess I can understand it making development a bit easier (not having to tie each charge to an individual user) but they should have a warning that when you delete a user that you should also remove a license if that is your intention.
If you have an infinite amount of money (from Oil), burying your freeways is a great idea. Google maps gets confused in those tunnels though, at least it did for me.
I recently canceled NYT by email in one round.
No. Did you look at the patent? "Optional chaining" is not one of the patent's claims.

The patent is about building a compiler out of 2 modular front-ends – each taking an input language (one being an OO language based on C), generating the appropriate IR, and handing the IR to a backend.

It goes on to specify that one of the integrated frontends does more compile-time safety checking, calling out bounds-checking and optionals, and the other doesn't (because it is specifically based on C).
Put aside the scoring and conclusion parts, the author has a couple interesting observations that resonate with me:

> ... but conscientious developers will be interested in doing things right. They’ll spend hours Googling for examples, trying to learn how to type things that TypeScript simply can’t type properly.

> ... if you only need to hire one or two developers, using TypeScript may make your opening more attractive to almost half the candidate pool.

On the other hand, it seems that the author worked on a few medium-size projects and then moved on:

> All projects for which impact was judged were >50k LOC with several collaborators working over several months.

So I wonder if he was able to evaluate the impacts from a longer term perspective, which shall include refactoring experience, iteration speed, developer morale, etc.
I think part of the speed of APL is the way that parts of it are small enough to fit in L2 cache (at least 1 of the APL descended languages, Q / K, bragged about this). Whether the Go implementation seen here will fit in typical caches of today's CPUs I don't know.
Zuck knows the average Facebook use is a "fucking dumbass", hence this is nothing more than his way of pacifying the herds. To give up precise targeting is to leave a lot of money on the table and a drop in share value. There won't be any drastic changes any time soon.
Slack faces growing challenge from Microsoft
You shouldn't take everything so serious, dude. Relax. Enjoy. It's fun.
Jinko's polycrystalline cells are so thin as to be almost impossible to keep from breaking, something on the range of 150um. I've got a few sitting here on my desk. Even an ultra-low pressure vacuum pick and place breaks them half of the time.
Without paywall: https://outline.com/zvEjNy
Of course any UNIX-like worth its salt is going to support Copy on Write and whatnot. But even then, forking is still quite slow relative to not doing anything at all.

Here's my point of view:

1. Forking is first and foremost a system call. (To be fair, I realize even memory allocation is much of the time, but still.) The kernel is going to do a bunch of work (as fast as it can, of course) and you're going to end up with two different OS level tasks by the end.

2. Those two tasks are now scheduled in tandem by the OS scheduler. For two tasks, this is fine. For hundreds of tasks, it becomes less effective. Threads will rapidly go in and out of I/O wait and the scheduler has to balance all of this.

3. CGI dies right here, though: CGI is not just a fork. It is a fork and exec! The exec, of course, also run in the kernel. It's going to effectively load the binary from scratch. Then you probably hit the linker in usermode, which has to go through the shared library resolution, resolving and mapping shared objects into memory and filling out import tables. This stuff has some caching as far as I know, but still... it's not free.

4. Now you are in the entrypoint of your program... or are you? If you are using CGI with Perl or Python or even Bash, we're not done yet because the script interpreter has to load all of its state from scratch, parse your script, bla bla, and THEN finally we can run your program.

5. Your application now has to do all of its common setup. Every. Connection. If you need to connect to a database, you can't connection pool: you have to open a new socket every time. Redis? same thing. Need to read a config file? Yep, every dang time. You can hack around some of this but in general it's probably going to be like this for most CGI applications. There's a reason why FastCGI exists after all.

The forking model of servers is elegant... but it doesn't work so well in my opinion. The cost of OS-level context switching is non-trivial, forking is relatively expensive, and things get worse when you are talking about something like CGI where your app effectively gets loaded from scratch each time.

My favorite model is definitely the Go model, where the language schedules lightweight threads or fibers across n OS threads (where n = number of logical threads.) It is cheap for the OS scheduler, and the language scheduler can very efficiently deal with things like I/O blocking and GC without huge latency hits.

But you can go about it many ways. Node.JS's event loop model proves pretty effective. Node is far from perfect but I think I would bet on a Node.JS server with a proper event loop over a CGI server forking a C program, myself.

Of course I'm really no expert. But, I think the jump from CGI to FastCGI told me all I need to know: CGI just didn't scale well at all. FastCGI was a much better experience for me, though I no longer use it.
It's not even maintained and the official site seems long gone. How do you see this as alive?
Huh.

Optics are modeled by differential equations. They describe a massively parallel phenomenon, light waves passing through and being modified by layers of media that, essentially, performs calculations using them. Warps and scales and so on. Clearly these particular differential equations are highly robust to architectural changes.

There's a parallel there to something else I've read about on Hacker News... what are those things called? Oh yeah, deep networks.

Are there any deep nets out there that attempt to mimic optics? or is anyone applying ideas from robust differential equations to deep nets?
A couple things Facebook could do:

Planning a party? Ad of a buffet local to the party location.

Promoting your band? How about a new guitar?

Stones fan club? Heard of their latest album?

Reading a post about nature? BAM! Outdoor gear!

Disclaimer: I don't actually use Facebook.
Yeah, it's definitely not a perfect system. I say this as my wife is currently on maternity leave. We've definitely adjusted our budget and had to plan accordingly.

The biggest point that I try to make when describing the system is that it's not a government handout, it's just an extension of unemployment insurance.

The idea of increasing deductions to bring up EI values seems reasonable, although I imagine it could be a hard sell for men who never intend to use it (not saying that's a reason to not do it, however I'm sure there would be opposition). An opt-in system could be better, but then that kind of goes against the idea of insurance (you'd likely only opt in if you knew you'd be needing it and it'd be advantageous to do so). I guess the argument against the idea would be "just save your money instead" which would bring us right back to where we are today.
Curvature doesn't change.

The UK has or at least had the ability to order online scriptless, it's not exactly anarchy over there.

Also as mentioned I can order 10 years of contacts with one 'valid one year' script.
I live in the tropics, and have fungi growing inside my lenses. They leave visible spots all the time, but photoshop takes care of that.
Legislation is stuck at the money-in-money-out mechanic.
Speak for yourself; I hate being manipulated.
I don’t mind Dropbox’ effort for trying to make users change the mind (I’m biased as an ex Dropboxer) and maybe the pattern is a little Grey but it only takes you 45 seconds to unsubscribe.. in contrast I has a much much worse experience with “I Done This” (idonethis.com) where I subscribed for me and one of my colleagues but somehow other people in my company that I didn’t know or work with (without me really knowing clearly - not sure what happened) were somehow able to become part of my “team” license and I got a big fat bill from them.. we didn’t even use the product and there was no negotiations whatsoever - not even an invoice section/download option in the product so no way I even had any kind of “receipt” for expense claims - the customer experience and cancellation process was the worst I’ve seen in a long time!! I’m pretty sure I had to email them to cancel in the end as well. Biggest issue was bill shock by new accounts being added to my subscription though. At least with Dropbox if you’ve subscribed in error or have very good reasons they’re usually not too strict on refunds - they try and go the extra mile unlike idonethis.com
honestly I think gambling could be a good thing for a child if they use money they've worked hard for themselves. sooner or later they will suffer a bad loss and have no new toys for a while. maybe give them some "margin" too to really get the point home.
While plenty of the article is sensible, the author unfortunately skips very briefly past the one killer situation.

It's not enough to say "[Transaction restart gets a little tricky in nondeterministic systems if some of the volatile state associated with a transaction that was lost during a failure was observed by other machines that did not fail. But there are simple ways to solve this problem that are out of scope for this post.]"

Any distributed system has the potential to completely loose some state ... say halfway through a transaction coordinating 2 servers, one bursts into flame and is completely destroyed, along with its non-volatile storage (log files). The other server must rollback (abort) the transaction or we all accept the system is no longer consistent.

There are no known ways to resolve this problem. Either accept the risk, or manage it outside the computer system.

PS. Don't bother adding extra phases to 2PC, that just delays the decision. The extra phases can't provide any definitive commit/abort answer more than would have been provided by 2PC.
Hoare notation literally made formally verified programs possible. The man is a great.
Just thought I'd point out that a lot of the reason companies make it so hard to cancel subscriptions is that it literally is a more "brutal" change for them when it comes to accounting, and what they have to report back to investors.

Recurring income is more highly valued than one-off / extraordinary income. Most traditional companies (telecom, banks, even gyms) have been this way, backing off only when forced to by regulation. It's sad, but not surprising to see the newer breed of companies also adopt these practices.
Seems useful! Remind me of pushpin.
Ha ha, true! :) but i felt your point was good, there is an upside to the fact we are acknowledging the state of affairs as it is.
This may make Washington and Ottawa feel good (Because it lets both sides save face), but is going to be pretty shitty for the people living in said territory, if it ever goes back to being split.

If it will never be re-split, then it's a de-facto annexation. In which case, I'd prefer that the residents vote on it.
I have long wished someone, ideally Apple, would successfully implement micropayments for news.
No, I went by the posted link. It does't alter my point.
Complete Short Stories of Ernest Hemingway
They don't. Facebook can join the club everyone else is in - having to get by on standard ads... or pioneer a new business model that makes it possible.

I'm not going to cry over Facebook making a few billion less considering the degree to which traditional journalism has been demolished by the reduced margins on internet advertising, and how much they encourage spreading clickbait and misinformation.

I'm not sure Twitter needs to exist, either.
They wouldn't let me cancel until I answered the question "how are you doing today?" I said "I want to cancel" but they just repeated the question until I finally said "fine" and then the conversation could proceed. Fun times.
If I can identify some other city that has been under liberal democrat control for decades and isn't dysfunctional, then it's not irrational for me maintain my ideology while asking for better from this one.
If you haven't done so already, would you recommend going through the old lessons? Or is the current version good enough?
Is it too late to force the fcc to back out of 5g approval?
Snapdocs (YC W14) Is Hiring a Lead Product Designer – We Power Homeownership
Like the FBI isn’t equally corrupt.
Oslo decided to make its downtown basically car-free?
I want to cancel my subscription. I don't want to explain why to a pleading sales rep telling me about all the great things I'm going to miss while they "pull up my account".
Good time to plug this utility, swiss army knife for websockets: https://github.com/vi/websocat
Author is extremely nice as well.