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(Author here) As far as I know, there are no cases where this actually matters.


In your post you say that a PSPACE algorithm exists. Do you have a reference for that algorithm ?

Another commenter here is saying the problem has an explicit exponential or worse lower bound.

If both of those claims are true that would prove P != PSPACE, which would be a very important result.


Yeah, afaik this problem is totally unimportant in practice.


Wait until it ends up being used in some other important field of math.


Good question :) The difference is that in that case, the problem might take a long time because the input is very long, but in this case, the problem might take a long time even if the input itself is fairly short.


(I am a former Triplebyte employee) The Triplebyte process also involves talking to an actual person; how are you proposing to game that?


This app sounds really cool!

I installed it but wasn't too impressed with the quality of the emoji. (This could be because I look kind of weird; eg I have pink hair.) It's really easy to take photos and see how the emoji look; I encourage other people to try that out.

I'm excited to see whether this technology ends up working well in future.


hey!

yea we don't have pink hair – basically it was really hard to get the color palettes working right in all kinds of different lighting conditions, so we didn't include rare/custom hair.

we'll get better at it :) thanks for using the product!!


The first part is real, and the second part is the joke.


Here's what Larry Summers had to say on this topic:

> 'Dirty' Industries: Just between you and me, shouldn't the World Bank be encouraging MORE migration of the dirty industries to the LDCs [Least Developed Countries]? I can think of three reasons:

> 1) The measurements of the costs of health impairing pollution depends on the foregone earnings from increased morbidity and mortality. From this point of view a given amount of health impairing pollution should be done in the country with the lowest cost, which will be the country with the lowest wages. I think the economic logic behind dumping a load of toxic waste in the lowest wage country is impeccable and we should face up to that.

> 2) The costs of pollution are likely to be non-linear as the initial increments of pollution probably have very low cost. I've always thought that under-populated countries in Africa are vastly UNDER-polluted, their air quality is probably vastly inefficiently low compared to Los Angeles or Mexico City. Only the lamentable facts that so much pollution is generated by non-tradable industries (transport, electrical generation) and that the unit transport costs of solid waste are so high prevent world welfare enhancing trade in air pollution and waste.

> 3) The demand for a clean environment for aesthetic and health reasons is likely to have very high income elasticity. The concern over an agent that causes a one in a million change in the odds of prostrate[sic] cancer is obviously going to be much higher in a country where people survive to get prostrate[sic] cancer than in a country where under 5 mortality is 200 per thousand. Also, much of the concern over industrial atmosphere discharge is about visibility impairing particulates. These discharges may have very little direct health impact. Clearly trade in goods that embody aesthetic pollution concerns could be welfare enhancing. While production is mobile the consumption of pretty air is a non-tradable.


It's actually what a grad student said about a topic that Summers later signed onto as part of a broader report... and you left out the last and most important paragraph which belies that the thing was written as a satirical critique of opponents of Liberalization and of the economists who insist on measuring everything in purely monetary terms. The last paragraph:

> The problem with the arguments against all of these proposals for more pollution in LDCs (intrinsic rights to certain goods, moral reasons, social concerns, lack of adequate markets, etc.) could be turned around and used more or less effectively against every Bank proposal for liberalization.

There are plenty of reasons to dislike Summers and to distrust the World Bank, but you should recalibrate your sarcasm detectors if you think a left-leaning economist (he's the nephew of Paul Samuelson and Kenneth Arrow.. I mean..) earnestly wrote "I think the economic logic behind dumping a load of toxic waste in the lowest wage country is impeccable and we should face up to that."



It took me 'til "Africa is inefficiently under-polluted" to realize it was satire.


Clearly a "modest proposal".


Whatever helps him sleep, I guess, but I don't think I can go along with this.


It's satire.


OK, then they got me. Too similar to something someone would actually write.


Poe's law strikes again.


This man is bad and he should feel bad.


"At around 1,000,000 elements our unsorted vector takes around 32 minutes to lookup a string."

I don't at all believe that C++ can only iterate through 2000 strings a second. Python takes an imperceptibly small time to iterate through an array of a million strings when I test it out in my repl, and I imagine C++ would either be as fast or somewhat faster. This number is so ridiculous that it makes me very skeptical of the rest of the article.


The x-axis is the number of iterations, i.e. the number of lookups. The collection is always size 1,000,000. Also, each of those lookups is for the exact same entry, so after the first time, it'll be all cache hits. Well, except for the std::vector, which is what you're talking about... :)


Strings are length 10 to 100. A cache line is 64 bytes. A cache miss is < 1000 cycles < 10^3ns. That makes < 1s for 10^6 strings.

Furthermore adjacent strings are likely to be adjacent in memory, from which I would naively expect cache prefetching to succeed.

Additionally, the curve is quadratic (if at all), not linear. I bet the author looked up all n strings from the vector of n strings.


I think the curves are linear because the x-axis is log scale but the y-axis is not.


Gotcha. It's probably still quadratic, just judging from the values. You can't need 32 minutes for 10^6 100-byte comparisons (which typically abort after the first character compares unequal. Not that that matters).


It's definitely a strange set of graphs:

Mixed (log/linear) scales on the axes

Only two columns of points on each graph matter (the last two) because the left hand side is all zeros (an artifact of the y axis not being log scale)

The y-axis is sometimes in thousands-of-mega-nanoseconds (with two significant digits) or sometimes in giga-nanoseconds (with one).

Giga-nanoseconds are seconds!

The colors for each line sometimes changes between graphs.


This list is an awkward mix of posts containing easily-verifiable but surprising claims about various technical specifications, and posts which just make a variety of contentious claims with no particular evidence provided (I think the economics one is possibly the worst).


Falsehoods programmers believe about gender is a pretty great example.


A great example of what? From what I read in there, each of those falsehoods is verifiable. Which one(s) (is/are)n't?


It's a pretty great example of falsehoods programmers believe.


The ideological ones are really horrible.


Which ones are ideological?


Most of the Human Identity section and the Society section.


But that makes no sense--if you want high social mobility (and you think college grads should be paid more), you want both those numbers to be lower. The article treats it as a problem that they're similar.


I agree. I actually think this whole article is just a puff piece; the premise makes no sense.


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