pjscott

27 ms·

301.
by pjscott 5y ago
It's not that hard to estimate the payload of a rocket once you know its dry mass, amount of propellant, and specific impulse. Which SpaceX does.
302.
by pjscott 5y ago
China and South Korea can build nuclear plants at a per-megawatt capital cost similar to coal plants, so I agree that the problem looks political.
303.
by pjscott 5y ago
> The author is saying that this would work as expected, with offspring gaining around 50% of their parents' extra longevity. Not for lifespan. What the author didn't mention is that this equation works for traits affected by a
304.
by pjscott 5y ago
It's been found empirically that IQ and educational attainment are moderately correlated.
305.
by pjscott 5y ago
> (surely it's logistically impractical to get any large number of busy faculty to spend time taking such tests) You can estimate it decently by looking at SAT scores, which most professors will have taken at some point. Your error
306.
by pjscott 5y ago
The usual studies for disentangling genetics and environment involve twins raised together: they get basically the same shared environment -- this is a feature, not a bug -- but identical twins are more closely related than fraternal twin
307.
by pjscott 5y ago
China is building a whole lot of new reactors, and the ones that came online most recently took about 5-6 years from start of construction to finish, which is substantially less than a decade. Japan, prior to the shutdown, was able to build
308.
by pjscott 5y ago
That goes back at least to the Gutenberg Bible, which was two columns per page with generous margins for annotation or hand-drawn decoration.
309.
by pjscott 5y ago
There has been remarkably little English linguistic drift since the widespread adoption of the printing press.
310.
by pjscott 5y ago
One of the best database habits I've ever developed is to run EXPLAIN on every query that I expect to run repeatedly, then sanity-check the output. It's very little effort, and has prevented so much hassle.
311.
by pjscott 5y ago
That sounds plausible on the face of it, but when I went looking for counterexamples they weren't hard to come by. Supermarkets, big box stores like Walmart, and online retail giants like Amazon all run centrally-managed logistics oper
312.
by pjscott 5y ago
Sierra Nevada Corporation and Boeing have been making miscellaneous space systems for decades. Maybe neither SNC nor Blue Origin will be able to deliver on their launch system promises, but it seems plausible that they could make a space st
313.
by pjscott 5y ago
> Intelligence is certainly a major factor but external factors such as having a stable home with quiet times that are conducive to studying, good nutrition, good role models, and good teachers play a major role as well. Tests like Raven
314.
by pjscott 5y ago
Most of the recent construction of large nuclear plants is in China, and they're actually doing quite well at building them on time. The ones that are super late and over budget are the exception worldwide; they just make the news more
315.
by pjscott 5y ago
Are taxpayers funding the government? Last year, federal tax revenues were $3 trillion less than federal spending.
316.
by pjscott 5y ago
There are economies of scale. There are also diseconomies of scale: https://en.wikipedia.org/wiki/Diseconomies_of_scale Inertia and institutional sclerosis are serious problems for organizations that are large, old, or
317.
by pjscott 5y ago
Wait, what? The asset classes with the highest rates of return over the past decade have all been equities, i.e. actually investing it in the economy: https://advisor.visualcapitalist.com/asset-class-risk-and-re... Letting
318.
by pjscott 5y ago
As an example of diversity of approaches, look at the Fast Grants program: https://future.a16z.com/what-we-learned-doing-fast-grants/ It was created in 2020 to give grants for COVID-related research. Its big selling po
319.
by pjscott 5y ago
That's a puzzling empirical claim. Why would no billionaires care about other people's problems?
320.
by pjscott 5y ago
> What you are ignoring is that government is more involved in colleges in these other countries and they manage to keep it under control. Again, how is the US screwing up whereas everyone else has it working properly? You haven't a
321.
by pjscott 5y ago
> - Nuclear plants take ages to build, and are insanely expensive. If you look at the list of reactors in the article, most of them took only 5-6 years to build. Between 1977 and 1987, a ten-year span of time, they added 45 GW of nuclear
322.
by pjscott 5y ago
I often hear opponents of nuclear power say that it takes too long to construct, so it's interesting to look at the timelines for these reactors -- most of them took about 5-6 years from the start of construction to being hooked up to
323.
by pjscott 5y ago
JS startup time also includes parsing the code and (initially) running in a very low-optimization mode, usually a bytecode interpreter, while the VM gathers profiling data in preparation for later JIT compilation of hot spots. This can be a
324.
by pjscott 5y ago
The compiler used, Clang 13.0.0, does indeed optimize out everything except for the "return 0;" at the end unless you compile with -O0 to disable optimization. I'm not sure whether the author benchmarked with -O0 or benchmark
325.
by pjscott 5y ago
The old JS interpreters were actually quite slow! That's why they made V8 in the first place. Speed was its big selling point.
326.
by pjscott 5y ago
Apparently NASA's inflation-adjusted budget has been about half of its Apollo-era levels ever since the 1970s: https://en.wikipedia.org/wiki/File:NASA_budget_linegraph_BH.... That's not as much, of course, bu
327.
by pjscott 5y ago
The blog post is putting the blame on a bug in the tooling which should have made the command impossible to issue, which is exactly where the blame ought to go.
328.
by pjscott 5y ago
People argue a lot about governments making decisions they disagree with, but something that I think is under-appreciated is the damage from unpredictable decisions. If you know how the government is going to act on some issue, for better
329.
by pjscott 5y ago
Beyond the really elementary things that get repeated often enough and insistently enough for most people to learn them whether they're interested or not -- basic reading, basic writing, addition and subtraction -- yes, as far as I can
330.
by pjscott 5y ago
I second the recommendation of the /r/personalfinance wiki. In particular, their FAQ answer to "I have $X, what do I do with it?" is a concise, simple-to-follow basic blueprint for handling money that should work well fo

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