Posts

Link Summary: Top 10 Replicated Findings from Behavioral Genetics 2020-04-19T01:32:43.000Z · score: 15 (7 votes)
Operationalizing Newcomb's Problem 2019-11-11T22:52:52.835Z · score: 36 (12 votes)
Is the World Getting Better? A brief summary of recent debate 2019-02-06T17:38:43.631Z · score: 35 (14 votes)

Comments

Comment by erickball on Nicotinamide riboside vs. SARS-coV-2 update · 2020-10-02T23:51:06.687Z · score: 2 (2 votes) · LW · GW

Hey, do you know if there are any results on the human or animal trials yet? I haven't been able to find anything, even though it's been a few months and it seems like initial data ought to be coming in.

Comment by erickball on Babble challenge: 50 ways of sending something to the moon · 2020-10-01T15:18:20.215Z · score: 1 (1 votes) · LW · GW

#24 made me laugh

Comment by erickball on Babble challenge: 50 ways of sending something to the moon · 2020-10-01T15:13:56.168Z · score: 1 (1 votes) · LW · GW

I love #24 and #41

Comment by erickball on Babble challenge: 50 ways of sending something to the moon · 2020-10-01T14:23:25.392Z · score: 12 (5 votes) · LW · GW

Okay well it took me more than an hour to get to 50, but still a great exercise!

1. Chemical rocket

2. Launch off of space elevator beyond geosync

3. Giant balloon (aim carefully you can't steer)

4. Coilgun

5. Launch loop (seriously how has nobody built this yet)

6. Railgun

7. Nuclear thermal rocket

8. Electric (ion) rocket powered by capacitors or batteries (ok might be a little heavy)

9. Electric (ion) rocket powered by lasers from the ground

10. Ablation rocket powered by lasers from the ground

11. Spaceplane combined with any of the rocket types, especially ablation rocket

12. Giant crossbow

13. One of those extending boxing glove toys with all the struts forming parallelograms (apparently this mechanism is called a "pantograph")

14. Series of nested giant crossbows: each one shoots a smaller crossbow

15. Hitch a ride on a passing asteroid using a tether

16. Use superconductors to levitate a flux-pinned magnet to the moon

17. Fusion rocket

18. Project Orion-style nuclear bomb rocket

19. Run a tether from the moon to the earth, and just let the tip drag along the ground and you can attach climbers to it as it goes by every day

20. Antimatter rocket

21. Ramjet

22. Bussard ramjet

23. Trebuchet

24. Bubble cavitation in a vacuum (could launch a tiny particle at high velocity from LEO)

25. Light gas gun

26. Plasma gun? Is that a thing?

27. Combination balloon and solar sail. The balloon lifts the solar sail until the air is too thin to keep rising, and then the sail takes off.

28. Build a giant radiotelescope to contact space aliens and ask them to carry something to the moon for you.

29. Ablation rocket powered by the sun (using dry ice maybe)

30. Hack the simulation and add code to teleport stuff on your command

31. Build a space elevator on the moon and use it to launch chunks of rock constantly towards earth, which you catch with a see-saw contraption to launch something smaller back the other way

32. Nuclear explosion underground that launches a big chunk of steel through a borehole, like in Operation Plumbob (have to use something longer and tungsten-coated so it doesn't vaporize)

33. Light sail powered by lasers from the ground

34. Use lightning to superheat pressurized gas in a massive gun chamber

35. Kite that turns into solar sail once it clears most of the atmosphere

36. Build a giant tower from Earth that reaches almost to the moon, with a vacuum chamber inside so it can be supported by an electron beam, and then just toss things from the top

37-39. Practice, practice, practice

40. Get that arm surgery that lets pitchers throw faster than they did before they were injured, but like 50 times

41. Stow away on the next moon launch

42. Bring the moon to you: rob the Earth of its rotational energy by over-using your space elevator, and the moon will slowly drift closer due to tidal locking (I think)

43. Fake a Dr. Evil-style terrorist threat to force the government to send people to the moon to stop you.

44. Rename your home to "the moon"

45. Something with carbon nanotubes (grow them to the moon I guess?)

46. Great great great great great pyramid

47. Drink way too much coffee in order to come up with more ideas (recursive self-improvement technique?)

48. Nuclear-powered jet engine that builds up momentum by circling the Earth a bunch of times like superman, at slightly higher altitude each time

49. Some kind of reactionless drive based on Hawking radiation

50. Just send neutrinos to the moon, nothing will stop them. (You are already doing this.)

Comment by erickball on Covid 9/10: Vitamin D · 2020-09-30T16:48:09.641Z · score: 2 (2 votes) · LW · GW

I eventually sent them this article, not ideal but good enough:

https://medium.com/microbial-instincts/the-first-clinical-trial-to-support-vitamin-d-therapy-for-covid-19-906a9d907468

Comment by erickball on Covid 9/10: Vitamin D · 2020-09-14T14:09:44.093Z · score: 2 (2 votes) · LW · GW

I would love to have a link to send my parents to convince them to take Vitamin D as a prophylactic. The one RCT, as noted above, has various issues that make it not ideal for that purpose. Does anyone know of an article (by some sort of expert) that makes a good case for supplementation?

Comment by erickball on How hard would it be to change GPT-3 in a way that allows audio? · 2020-08-28T15:30:21.553Z · score: 2 (2 votes) · LW · GW

Since the same transformer architecture works on images with basically no modification, I suspect it would do well on audio prediction too. Finding a really broad representative dataset for speech might be difficult, but I guess audiobooks are a good start. The context window might cause problems, because 2000 byte pairs of text takes up a lot more than 4000 bytes in audio form. But I bet it would be able to mimic voices pretty well even with a small window. (edit: Actually probably not, see Gwern's answer.)

If your question is whether the trained GPT-3 model could be modified to work with audio, I suspect not. In principle there are layers of abstraction that a transformer should be able to take advantage of, so that word prediction is mostly uncoupled from audio processing, but there's not a perfect separation, and we wouldn't know how to interface them. Maybe you could train a separate transformer model that just transcribes audio into text, and stitch them together that way, but there's not much reason to think it would be a big improvement over existing speech recognition systems.

Comment by erickball on The Fusion Power Generator Scenario · 2020-08-11T21:24:11.967Z · score: 1 (1 votes) · LW · GW

Weapons grade is kind of a nebulous term. In the broadest sense it means anything isotopically pure enough to make a working bomb, and in that sense Little Boy obviously qualifies. However, standard enrichment for later uranium bombs is typically around 90%, and according to Wikipedia, Little Boy was around 80% average enrichment.

It is well known that once you have weapons-grade fissile material, building a crude bomb requires little more than a machine shop. Isotopic enrichment is historically slow and expensive (and hard to hide), but there could certainly be tricks not yet widely known...

Comment by erickball on Noise on the Channel · 2020-07-03T02:15:03.503Z · score: 3 (2 votes) · LW · GW

I'm a big fan of crowd noises for improving concentration when you need to drown out other voices, especially a TV. Much more effective than other forms of white noise.

Comment by erickball on List of public predictions of what GPT-X can or can't do? · 2020-06-17T03:45:07.976Z · score: 3 (2 votes) · LW · GW

I think your formatting with the semicolons and the equals sign has confused the transformer. All the strange words, plurals, and weird possessives may also be confusing. On TTT, if I use common words and switch to colon and linebreak as the separators, it at least picks up that the pattern is gibberish: words.

For example:

kobo: book ntthrgeS: Strength rachi: chair sviion: vision drao: road ntiket: kitten dewdngi: wedding lsptaah: asphalt veon: oven htoetsasu: southeast rdeecno: encoder lsbaap1: phonetics nekmet: chic-lookin' zhafut: crinkly lvtea: question mark cnhaetn: decorated gelsek: ribbon odrcaa: ribbon nepci: ball plel: half cls: winged redoz: brightness star: town moriub:

Comment by erickball on Everyday Lessons from High-Dimensional Optimization · 2020-06-12T01:39:15.633Z · score: 3 (2 votes) · LW · GW

It seems like the situation with bridges is roughly analagous to neural networks: the cost has nothing to do with how much you change the design (distance) but instead is proportional to how many times you change the design. Evaluating any change, big or small, requires building a bridge (or more likely, simulating a bridge). So you can't just take a tiny step in each of n directions, because it would still have n times the cost of taking a step in one direction. E. Coli is actually pretty unusual in that the evaluation is nearly free, but the change in position is expensive.

Comment by erickball on Sparsity and interpretability? · 2020-06-10T17:51:34.988Z · score: 1 (1 votes) · LW · GW

I like this visualization tool. There are some very interesting things going on here when you look into the details of the network in the second-to-last MNIST figure. One is that it seems to mostly identify each digit by ruling out the others. For instance, the first two dot-product boxes (on the lower left) could be described as "not-a-0" detectors, and will give a positive result if they detect pixels in the center, near the corners, or at the extreme edges. The next two boxes could be loosely called "not-a-9" detectors (though they also contribute to the 0 and 4 classifications) and the three after that are "not-a-4" detectors. (The use of ReLU makes this functionally different from having a "4" detector with a negative weight.)

Now, take a look at the two boxes that contribute to output 1 (I would call these "not-a-1" detectors). If you select the "7" input and see how those two boxes respond to it, they both react pretty strongly to the very bottom of the 7 (the fact that it's near the edge) and that's what allows the network to distinguish a 7 from a 1. Intuitively, this seems like a shared feature--so why is the network so sure that anything near the bottom cannot be part of a 1?

It looks to me like it's taking advantage of the way the MNIST images are preprocessed, with each digit's center-of-mass translated to the center of the image. Because the 7 has more of its mass near the top, its lower extremity can reach farther from the center. The 1, on the other hand, is not top-heavy or bottom-heavy, so it won't be translated by any significant amount in preprocessing and its extremities can't get near the edges.

The same thing happens with the "not-a-3" detector box when you select input 2. The "not-a-3" detector triggers quite strongly because of the tail that stretches out to the right. That area could never be occupied by a 3, because the 3 has most of its pixel mass near its right edge and will be translated left to get its center of mass centered in the image. The "7" detector (an exception to the pattern of ruling digits out) mostly identifies a 7 by the fact that it does not have any pixels near the top of the image (and to a lesser extent, does not have pixels in the lower-right corner).

What does this pattern tell us? First, that a different preprocessing technique (centering a bounding box in the image, for instance, instead of the digit's center of mass) would require a very different strategy. I don't know off hand what it would look like--maybe there's some trick for making the problems equivalent, maybe not. Second, that it can succeed without noticing most of what humans would consider the key features of these digits. For the most part it doesn't need to know the difference between straight lines and curved lines, or whether the parts connect the way they're supposed to, or even whether lines are horizontal or vertical. It can use simple cues like how far each digit extends in different directions from its center of mass. Maybe with so few layers (and no convolution) it has to use those simple cues.

As far as interpretability, this seems difficult to generalize to non-visual data, since humans won't intuitively grasp what's going on as easily. But it certainly seems worthwhile to explore ideas for how it could work.

Comment by erickball on Open & Welcome Thread—May 2020 · 2020-06-04T04:22:48.722Z · score: 1 (1 votes) · LW · GW

I like LearnObit so far. We should talk sometime about possible improvements to the interface. Are you familiar with quantum.country? Similar goal, different methods, possible synergy. They demo what is (in my opinion) a very effective teaching technique, but provide no good method for people to create new material. I think with some minor tweaks LearnObit might be able to fill that gap.

Comment by erickball on Restricted Diet and Longevity, does eating pattern matter? · 2020-06-02T15:31:29.332Z · score: 3 (2 votes) · LW · GW

Take a look at the Fasting-Mimicking Diet, which has some decent evidence going for it. It's a 5-day period of low calorie consumption with restricted carb and protein intake, repeated every few months.

Some people actually think the benefits of caloric restriction (to the extent there are any benefits in humans beyond just avoiding overfat) may result from incidental intermittent fasting. I'm no expert but my fairly vague understanding is that the re-feeding period after a fast promotes some kind of cellular repair process that doesn't occur if you're continuously well-fed. I guess people who restrict calories overall would generally get little doses of this every once in a while as their food intake fluctuates by chance.

Comment by erickball on Covid-19: My Current Model · 2020-06-02T13:57:20.343Z · score: 9 (2 votes) · LW · GW

Thank you for the dose of empiricism. However, I see that the abstract says they found "little geographic variation in transmissibility" and do not draw any specific conclusions about heterogeneity in individuals (which obviously must exist to some extent).

They suggest that the R0 of the pandemic flu increased from one wave to the next, but there's considerable overlap in their confidence intervals so it's not totally clear that's what happened. Their waves are also a full year each, so some loss of immunity seems plausible. I wonder, too, if heterogeneity among individuals is more extreme when most people are taking precautions (as they are now).

Comment by erickball on OpenAI announces GPT-3 · 2020-05-29T16:27:45.749Z · score: 10 (6 votes) · LW · GW

So, the paper title is "Language Models are Few-Shot Learners" and this commenter's suggested "more conservative interpretation" is "Lots of NLP Tasks are Learned in the Course of Language Modeling and can be Queried by Example." Now, I agree that version states the thesis more clearly, but it's pretty much saying the same thing. It's a claim about properties fundamental to language models, not about this specific model. I can't fully evaluate whether the authors have enough evidence to back that claim up but it's an interesting and plausible idea, and I don't think the framing is irresponsible if they really believe it's true.

Comment by erickball on Speculations on the Future of Fiction Writing · 2020-05-28T18:39:55.075Z · score: 17 (12 votes) · LW · GW

I wonder if there's actually any way to know if a movie that has better writing makes bigger profits. From what I've heard, the main thing that determines how much a film writer gets paid is a track record of writing successful films. This makes sense if the producers know they don't have good taste in screenplays--they just hire based on the metric they care about directly. But it also makes sense if the factors that affect how successful a screenplay is have very little to do with "taste" in the sense you mean. Maybe the writers of blockbuster films know that more intelligent characters won't affect profits, but (for example) faster pacing will, and so they ruthlessly cut out all those in-universe decision constraints that take up screen time. Maybe they even want the characters to be kind of dumb, to get the reality-TV effect where the audience gets to feel superior because they never would have been THAT dumb.

Comment by erickball on Why We Age, Part 2: Non-adaptive theories · 2020-05-28T17:46:37.052Z · score: 2 (2 votes) · LW · GW

But longer-lived animals get cancer less, not more. I've heard this theory before but I don't quite understand it. It seems to predict that age would be bounded by a trade-off against child cancers. But in fact selection seems to make animals longer-lived pretty easily (e.g. humans vs homo erectus). Naked mole rats barely get cancer at all, afaik. Do baby bats get cancer more than baby mice?

Comment by erickball on Why We Age, Part 2: Non-adaptive theories · 2020-05-27T16:02:30.365Z · score: 2 (2 votes) · LW · GW
Just over 50% of the lifetime expected reproductive output of a newborn elf is concentrated into its first 700 years; even though it could in principle live for millennia, producing children at the same rate all the while, its odds of reproducing are best early in life.

I think your elf example is even more extreme than you make it out to be, at least when population size is increasing, since the offspring an individual produces early in life can produce their own descendants exponentially while the original is limited to constant fecundity. 50% of an elf's expected direct reproductive output comes in the first 700 years (5.03 expected offspring). But the total number of descendants is exp((fecundity - mortality)*age) - 1, or about 544 expected descendants at 700 years. It's clear that (in this extreme case where fecundity is an order of magnitude higher than mortality) the death of the original at this point would make effectively no difference to the number of descendants going forward.

This effect should also apply to oscillating population sizes even if there's no net increase over time (probably a more typical situation in practice). However, it does not account for the infertile period at the beginning of an organism's life.

To be slightly more realistic, by the time aging seriously limits the ability to reproduce in humans (say age 40) a human could easily have multiple offspring old enough to reproduce. So even if extrinsic mortality is zero, a mutation that causes death or infertility at age 40 is reducing marginal reproductive output only by a fairly small fraction, which could be easily outweighed if it also increases fertility when young.

Comment by erickball on Why We Age, Part 2: Non-adaptive theories · 2020-05-27T14:30:45.170Z · score: 3 (2 votes) · LW · GW
Are you suggesting antagonistic pleiotropy is particularly non-obvious in humans (vs other animals), or that it's non-obvious generally but you particularly care about humans?

As far as proof that it can happen in general, I found the example of animals that live just long enough to reproduce pretty convincing. Salmon don't live more than about four years, but it's quite clear how they gain a fitness advantage from dying after they spawn. But that sort of thing is pretty rare, so the claim that it happens in a particular species with no such obvious mechanism (or indeed in practically all animals) is a little harder to swallow.

This sentence confuses me. Why would you expect it to be harmful early on?

I guess I put this sort of backwards. I meant that I would expect a mutation that causes tissue repair function to degrade with age to decrease fitness (slightly) overall, since there's no obvious connection to some beneficial effect earlier in life. Same with heart disease, sarcopenia, etc.

Comment by erickball on Why We Age, Part 2: Non-adaptive theories · 2020-05-27T04:58:50.201Z · score: 3 (2 votes) · LW · GW

Antagonistic pleiotropy is certainly plausible in the abstract, but it's not obvious how it would work in humans. Something like tissue repair, for instance, is obviously beneficial in old age but it's hard to see how it would be harmful early on. From googling a little bit, I found some info suggesting:

  • The adaptive immune system (because it "runs out of capacity" late in life; see also the discussion here)
  • Genes associated with coronary artery disease that appear to be under positive selection (but it doesn't say why)
  • A gene that causes premature cell senescence if you have multiple copies, but is useful for repairing UV-induced DNA damage

I'm curious if anybody knows of other examples of how this mechanism actually works out physiologically.

Also, it seems like this kind of explanation suggests we should be fairly pessimistic about finding a "cure" for aging, since there are likely many different unrelated causes. On the other hand, maybe it should make us optimistic about being able to gradually invent solutions to many of those causes individually, if they are created by selection rather than being fundamental/unavoidable consequences of our cellular metabolism or something.

Comment by erickball on Seasonality of COVID-19, Other Coronaviruses, and Influenza · 2020-05-04T03:35:16.225Z · score: 6 (4 votes) · LW · GW

Thank you, lots of good info in those links.

Comment by erickball on Against strong bayesianism · 2020-05-03T02:40:09.620Z · score: 3 (2 votes) · LW · GW

Are there any of them you could explain? It would be interesting to hear how that caches out in real life.

Comment by erickball on Seasonality of COVID-19, Other Coronaviruses, and Influenza · 2020-05-02T06:04:42.850Z · score: 5 (2 votes) · LW · GW

I would like to call attention to the conflict of interest statement at the end, where the senior author Charles Brenner is identified as chief scientific adviser of ChromaDex, maker of Tru Niagen, a profitable nicotinamide riboside supplement. I'm not saying the theory is necessarily wrong--NAD+ is implicated in many aspects of aging, and aging is obviously a risk factor for Covid mortality. But the effects of NR supplementation in humans have been a bit over-hyped in the past. Again, I don't mean to imply that it does nothing, but it has been pushed as an anti-aging supplement without good evidence for improvement of biomarkers other than NAD+. For instance this study found no effect on insulin sensitivity or other metabolic measures.

Comment by erickball on What are habits that a lot of people have and don't tend to have ever questioned? · 2020-04-21T14:35:55.806Z · score: 1 (1 votes) · LW · GW

What do you mean about junk drawers? Is this a metaphor?

Comment by erickball on Deminatalist Total Utilitarianism · 2020-04-19T15:16:03.116Z · score: 1 (1 votes) · LW · GW

Say you are in a position to run lots of simulations of people, and you want to allocate resources so as to maximize the utility generated. Of course, you will design your simulations so that h >> h0. Because all the simulations are very happy, u0 is now presumably smaller than hτ0 (perhaps much smaller). Your simulations quickly overcome the u0 penalty and start rapidly generating net utility, but the rate at which they generate it immediately begins to fade. Under your system it is optimal to terminate these happy people long before their lifespan reaches the natural lifespan τ, and reallocate the resources to new happy simulations.

The counterintuitive result occurs because this system assigns most of the marginal utility to occur early in a person's life.

Comment by erickball on The Hammer and the Mask - A call to action · 2020-04-19T14:23:39.769Z · score: 3 (3 votes) · LW · GW

The use of an exhalation valve means that the filter fails to capture some of the outgoing virus particles from the wearer's breath. Some types of N95 also have valves that cause the same problem. Depending on the positioning of the valve, maybe it's not a big problem? Or it might be easy to mitigate by covering it with cloth or something.

Comment by erickball on C19 Prediction Survey Thread · 2020-04-08T01:30:11.579Z · score: 3 (2 votes) · LW · GW

Update: it is the evening of April 7th and the latest data from plague.com has the US death count at 12,846. It looks like we'll hit 15,000 on the 9th probably, so I was a tad pessimistic. People have been talking about how new infections are slowing down and they think everything will peak in mid-April, but I don't see much reason to believe it. The trend continues much the way it was before.

Comment by erickball on Transportation as a Constraint · 2020-04-06T15:18:56.086Z · score: 5 (3 votes) · LW · GW

If transportation isn't a problem then transporting water/sewer/energy over long distances would presumably also be cheap, so buildings could share infrastructure without being colocated, right?

Comment by erickball on An alarm bell for the next pandemic · 2020-04-06T14:22:32.919Z · score: 6 (4 votes) · LW · GW

It would be nice if we had somebody who specifically agreed to check sites like that regularly and then let the rest of us know if there's something worth being concerned about. That way we could avoid duplication of effort.

Comment by erickball on What will happen to supply chains in the era of COVID-19? · 2020-04-02T13:17:53.932Z · score: 3 (2 votes) · LW · GW

Are those government-owned warehouses of grain like the ones Kaj mentioned in Finland? The US used to have a strategic grain reserve, although it looks like at the time it was liquidated in 2008 it had only 915,000 tons of grain, which would feed the country for... not even a week.

Requiring businesses that sell non-perishable food to store a few months' supply sounds reasonable, but I'm curious if other places have used that approach successfully. I know groceries are a low-margin business to begin with.

Comment by erickball on What will happen to supply chains in the era of COVID-19? · 2020-03-31T18:36:21.862Z · score: 15 (5 votes) · LW · GW

Pushback against just-in-time supply chains sounds appealing, but how would it actually work? Is this something we can regulate, maybe make grocery stores go through stress tests like the ones we do for big banks? Somehow I have a hard time believing practices will change.

Comment by erickball on C19 Prediction Survey Thread · 2020-03-30T18:45:37.282Z · score: 8 (5 votes) · LW · GW

May 1st prediction:

US deaths: lognormal(11.4, 0.5) mode: 69k -- this is roughly equivalent, per capita, to what Italy is at currently (March 30th). Therefore it assumes the current growth will slow considerably. 15k is not even on the radar. I expect we will hit 3000 today, and 15k around April 7th.

US confirmed cases: lognormal(15, 0.7) mode: 2 million. This is more uncertain because it largely depends on how fast we ramp up testing.

Comment by erickball on Price Gouging and Speculative Costs · 2020-03-28T01:32:50.804Z · score: 2 (2 votes) · LW · GW

Ah, okay. I guess that answers my question: you don't think it's possible to mitigate shortages by stockpiling without losing money in expectation. I wish it were--surge production is a much more tenuous solution that depends on being able to foresee a disaster shortly before it occurs, and even then it might not be possible to produce enough to help significantly.

Comment by erickball on Price Gouging and Speculative Costs · 2020-03-27T18:28:39.986Z · score: 2 (2 votes) · LW · GW
You're also in a morally worse spot - you run the risk that you are creating or amplifying the shortage, not just predicting and smoothing the consumption of rapidly-value-changing products. If you aren't solving the problem given in the post (you could make more, but not at your normal prices), you're not as clearly on the side of good.

I don't follow. The idea would be that you aren't contributing to the normal supply, you just stockpile in case of future emergency. This increases production during normal times slightly, and then when there is a pandemic you would stop purchasing and start selling. This reduces the need for manufacturers to produce more at higher marginal cost. How could it create or amplify a shortage?

It's true you'd have no profit prior to the emergency (and large costs) but in theory that shouldn't matter as long as your investors diversify.

Comment by erickball on Price Gouging and Speculative Costs · 2020-03-27T02:29:59.924Z · score: 2 (2 votes) · LW · GW

Is there a way to do this if you're not already a manufacturer? With, say, N95 masks--could we buy up a bunch of regular ones when there's no shortage, do something that costs a little money and adds a tiny bit of value (maybe print cute pictures on them for doctors who wear them around little kids) and then mark them up 900%? I mean, I don't have money to buy them with, but if stockpiling really makes economic sense then I'd think we could get investors to front it.

How do price gouging laws apply to discounted products? If we almost always offer an 80% discount, can we stop offering that during an emergency?

ETA: to be clear, masks are just an example. They would not be a good choice in the future because after this pandemic governments will actually stockpile them. We'd need to figure out what there's likely to be a major shortage of in the NEXT global emergency.

Comment by erickball on Authorities and Amateurs · 2020-03-25T20:04:43.144Z · score: 1 (1 votes) · LW · GW

It said the fraction would be a bit lower for the US because local outbreaks could be dealt with by state-level lockdowns, but I didn't see a hard number. Still, intermittent lockdowns for 18 months seems much more achievable than a continuous lockdown. The Hammer article is definitely more optimistic than the Imperial paper, though it still doesn't quite imply "return to normal".

Since "do nothing" is not a real option, what will actually happen in the US (I'm moderately confident) is some degree of lockdown for several weeks to several months depending on how effective it is. The sooner we start it the better it will work. After that we will either: 1) give up, if the lockdown was ineffective and a large fraction of the country is infected (this is "flattening"), or 2) if the lockdown succeeded in reducing the number of cases substantially, we'll move into a period of intermittent and possibly localized lockdowns interspersed with trying to test and contact trace. The fraction of time we spend in intermittent lockdowns will depend on how effective the testing and tracing is.

Comment by erickball on The Solution is Inaction · 2020-03-25T17:31:15.985Z · score: 3 (2 votes) · LW · GW

I've always thought the premium charged by landlords for the services they provide (roughly, the difference between rent and mortgage interest + taxes + insurance) is pretty small, though I don't have numbers on hand. Besides maintenance and property management stuff, they take quite a bit of risk of fluctuations in property values, damage to the building, tenants stopping payment (in which case eviction typically takes quite a while), and liability for accidents and the like.

Comment by erickball on Authorities and Amateurs · 2020-03-25T16:55:34.972Z · score: 1 (1 votes) · LW · GW

From the Imperial College paper:

For countries able to achieve it, this leaves suppression as the preferred policy option. [...] The major challenge of suppression is that this type of intensive intervention package--or something equivalently effective at reducing transmission--will need to be maintained until a vaccine becomes available (potentially 18 months or more)--given that we predict that transmission will quickly rebound if interventions are relaxed. We show that intermittent social distancing--triggered by trends in disease surveillance--may allow interventions to be relaxed temporarily in relative short time windows, but measures will need to be reintroduced if or when case numbers rebound.

So it's not really saying "lock down for 18 months or do nothing". It's saying lock down until the problem is controlled and then squash new outbreaks quickly. The Hammer and the Dance article makes this point more clearly in my opinion, especially pointing out that a temporary lockdown would give us time to build up test and treatment capacity, protective equipment supplies, etc, and implement strategies for tracing and suppressing the new cases that arise after it's lifted. However it does say "a few weeks" of strict lockdown will be enough without really supporting it well, and that seems optimistic (Bill Gates, for instance, has been saying 6-10 weeks).

Comment by erickball on The Solution is Inaction · 2020-03-25T01:03:20.733Z · score: 4 (3 votes) · LW · GW
On a tangent, I'm honestly not sure why we can't do option (1) with regard to rent, but for Chesterton's Fence reasons, I assume that landlords have to burn a certain amount of money per month in offering to the Elder Gods or else we will all die.

I don't see why you would expect landlords to have more extra cash on hand than anyone else? In the case of individuals who own one or a small number of properties, you'd expect them to have mortgages, and/or maybe living expenses if property management is their full-time job or they're retired. For larger businesses, they likely also have debt to service, plus employees and stuff.

Comment by erickball on What is the point of College? Specifically is it worth investing time to gain knowledge? · 2020-03-24T20:25:32.288Z · score: 2 (2 votes) · LW · GW

I guess I wasn't counting every little derivation or example or even formula that comes up in a class against that 90%. Those are things you see in lecture, but you don't "learn" them. The stuff you actually learn is concepts and techniques, like what you would need to answer the test questions. Even that stuff, of course, you'll mostly forget if you don't review it regularly. But... I'm not very confident that you can strip out all the stuff you're going to forget and still learn the stuff you would have remembered. I don't know of any real examples of this working. It seems like maybe the academic system of "present a whole bunch of info rapidly and then force students to study key ideas from it for homework and tests" might have become entrenched over time because it performs better than the obvious alternatives.

I would love to see evidence of something better, though. It seems like good use of spaced repetition is a non-obvious candidate to replace the lecture-homework-test system. If you haven't seen quantum.country, that's the kind of thing I'm thinking of and my initial experience with it is promising.

Comment by erickball on What is the point of College? Specifically is it worth investing time to gain knowledge? · 2020-03-24T15:10:20.606Z · score: 3 (3 votes) · LW · GW

I think 90% is an exaggeration, but even if you get a research job in the same sub-field as your graduate degree, it's true you probably will not be using the majority of your engineering course work. The problem is that you can't pick out the 20-30% you will benefit from and learn that in isolation. And I don't think judging on the basis of which courses you did or didn't like is a very good indicator (though admittedly there were some I disliked so much that I did badly and learned next to nothing). The way an engineering curriculum is structured is to let each topic build on past knowledge. Consider the class on statics that you probably took or are taking. Could you have understood bending moments and deflection of beams without first learning the concepts of derivatives and integrals? How about trigonometry? If you're like me, you've forgotten 90% of your high school trigonometry class, but if you hadn't taken it at all you'd really be struggling with the more advanced material.

I do think a lot of courses could be condensed down to a much smaller kernel of key concepts, which could be taught in far less than a semester and then retained with spaced repetition. If you have the impetus and self-discipline to design a system like that for yourself then it might be worth trying, with a couple of caveats. First, the credential of a degree is pretty important--more so in mechanical engineering than in computer science. Second, you want to choose a curriculum designed by someone who has already learned this stuff--you can't pick the topics yourself. And third, part of what you're doing when you take an engineering class is practicing application of key ideas. To return to trigonometry--we did lots and lots of proofs using trig identities. I have forgotten most of them, other than sin^2+cos^2=1. But I don't think it was all wasted, because I still derive formulas from geometric relationships sometimes, and I think it would be much more difficult and error-prone if I hadn't done a lot of that sort of thing in school. This is a small portion of my work hours but probably some of the highest-value work I do.

Here's another example from my experience. I was asked to build a simulation of a system based on some old photocopies of engineering diagrams. These included a big list of Laplace-domain controller coefficients and a diagram for a feedback system using lead and lag controllers. One of my colleagues had looked at it and didn't really understand what it meant so they ignored it. Luckily I had taken a controls class. I couldn't have defined a Laplace transform for you off the top of my head, but I could see how the controller fit into what we were modeling and figure out the gist of its purpose. My colleague could have borrowed a textbook, taken a few days to study control theory, and understood the system much better than I did. But even if that were practical in a business environment, you wouldn't know it was worth doing if you didn't have background knowledge of the topic. Did that (plus the few other times I've used control theory) make the whole course worth it? Maybe not in a naive calculation of time spent. But a big part of your value as an engineer is being able to recognize a problem and know where to look for the solution. If you have to call an expert for the solution that's often fine. But if you have to call in an expert to tell you what the problem is, well then they could have just skipped right past hiring you, couldn't they?

At one point I wrote some questions for a work-sample test to give to prospective hires at my company, with the goal of testing for general engineering competence. I don't know if they'd be helpful for demonstrating what I mean, but message me if you want to take a look at them.

Comment by erickball on What is the point of College? Specifically is it worth investing time to gain knowledge? · 2020-03-24T03:54:38.998Z · score: 3 (3 votes) · LW · GW

I agree with Dagon and johnswentworth's answers, and I would like to particularly emphasize one point. For me, as a mechanical engineer, most of the time I do not use most of the things I learned in school (and indeed I have forgotten most of them). Learning to do my job took months of studying field-specific stuff that most engineering schools don't teach. But if I had tried to learn it without first taking a lot of engineering courses, it would have taken years instead--and almost no company is willing to train someone for years. Think of education as turning yourself into a minimum viable product. It might be better in principle to intersperse work and school--either work as an engineer and then take time off to study, or do some study on the side. But you can't do either of those until you're skilled enough for someone to want to pay you.

Also, every now and then, some piece of knowledge from a course turns out to be useful, but you can't know in advance what it will be. If you haven't already studied it, then when the situation arises where you could use it you won't be able to tell; and you can't look something up unless you already know it's important.

Comment by erickball on Using smart thermometer data to estimate the number of coronavirus cases · 2020-03-24T01:22:25.913Z · score: 4 (2 votes) · LW · GW

I'm confused about the nature of the raw data here--if it's just spontaneous temperature-measurements, why would we expect it to show anything meaningful? They're showing a "% ill" which is presumably the percentage of people who took their temperature with a Kinsa thermometer recently who have a fever. But people generally only take their temperature when they think they might be sick. In a normal year, after calibration against some sort of ground-truth, I can see how you might still be able to use the data to track flu rates. But during a pandemic, won't people's pattern of temperature-taking completely change? I've taken my temperature way more in the last two weeks than I would normally (which is close to zero) and I bet the same is true for many other people. So the base rates will have changed a lot.

Comment by erickball on Loss of sense of smell as marker of COVID-19 infection · 2020-03-22T18:58:30.423Z · score: 1 (1 votes) · LW · GW

Does it say what the threshold we would use to determine if someone has anosmia?

Comment by erickball on When to Donate Masks? · 2020-03-22T18:56:07.315Z · score: 3 (2 votes) · LW · GW

Thank you, this exactly answers a question I had been wondering about. I have only about a dozen N95 masks and would like to donate them, but since my area is not hard-hit yet I'm imagining that they would each be used once and thrown out. I will wait a few weeks as you suggest.

Comment by erickball on March Coronavirus Open Thread · 2020-03-22T05:40:01.020Z · score: 2 (2 votes) · LW · GW

Hmm, maybe you're right. The South Korean distribution of cases by age here suggests that it's actually most common by far among people in their twenties, and the larger number of confirmed cases among older people is a statistical artifact resulting from test criteria. The data do look a bit suspicious though.

Comment by erickball on March Coronavirus Open Thread · 2020-03-21T16:20:03.457Z · score: 1 (1 votes) · LW · GW

You found an age distribution for the infected population on the Diamond Princess, but you're using it as if it's the age distribution for everyone on the ship. Older people are more likely to get infected, so the infected population in the US will lean older as well--closer to the distribution on the ship. To do a good age adjustment we need to know the ages of the people on the ship who were not infected.

Comment by erickball on Preprint says R0=~5 (!) / infection fatality ratio=~0.1%. Thoughts? · 2020-03-20T14:03:34.924Z · score: 1 (3 votes) · LW · GW

The ~1% infection fatality rate on the Diamond Princess (where everyone was tested) is pretty solid evidence against this.

Comment by erickball on How useful are masks during an epidemic? · 2020-03-17T20:36:40.959Z · score: 4 (3 votes) · LW · GW

You can see the fit-testing on youtube. It's pretty involved and not something you can do at home--they put a hood over your head and spray in a bunch of super-sweet aerosol, and if you can taste it through the mask then the fit isn't good enough.

On the other hand, they do that once a year, just to make sure that model is capable of fitting your face shape. The masks are supposed to be one-size-fits most. On a daily basis, the fit procedure is to put it on and blow out and see if you can feel any air escaping around your nose. This seems very achievable and likely to give a decent fit for most people.