Fama-French is not a “model of market efficiency.” Honest economists describe it as the best challenge to Fama’s theory of efficiency. Sometimes Fama tries to reconcile this model with efficiency by proposing that there is a fat tail of risk correlated with the anomalies, but this is just a hypothesis, a research program, not something that has any evidence beyond the anomaly.
Douglas_Knight
Karma: 7,320
I’ve also heard that past infection confers marginal immunity even in the presence of vaccination.
What do you mean by “marginal”? The most common meaning is “low,” and if that’s what you mean, you really need to know it’s false. But I guess you mean “additional.” That’s a pretty weird usage, though, because infection isn’t a margin that is easy to control, particularly if it comes before the vaccine (it would make more sense to switch the words “infection” and “vaccination”). There are lots of studies trying to measure how much protection infection + one shot gives. The most interesting is one that claimed that it provided substantial protection not just against sars-2 variants, but even against the quite distant sars-1. I’m not sure anyone has tested against delta, but protection against sars-1 is a pretty good substitute.
So why is this combination so broadly useful? One possibility is that actual infection is so different from vaccination that the body responds broadly, to encompass both. This possibility doesn’t give much practical advice, although mixing vaccines would provide a little diversity. Another possibility infection is just like a vaccination, but came much earlier and the long interval (8 months) produced broad immunity. Indeed, memory cells diversify over time. If this is the mechanism, then an additional dose could be valuable, not because it is additional, but because it is so much later. The time between doses might be more important than the number of doses, particularly for broad immunity, ie, for variants. Since the UK already has a longer vaccine interval than the rest of the world, they should be better protected against delta, so their success so far might not be such good news for the rest of the world.
One problem with positivity numbers is that positive tests are reported ahead of negative tests, so if there is a spike in testing, there will be a spike in reported positivity.
That sounds like an outside view argument, making the use of the example in general argument purely circular.
I don’t point out that the Difference Engine was more feasible. I specifically asked you for such an argument and you sidestepped. I don’t think anyone has ever made such an argument.
I only point out that the Difference Engine was feasible, which is an independent claim. For a century people claimed that Babbage’s designs were infeasible. This proves too much. Would you have made that mistake? If the construction disproved the conventional wisdom, it is not enough to minimally adjust your conclusions to avoid the falsehoods, but to adjust your methods.
Sure, Babbage didn’t finish the design, but how to you justify
could never have been built with the technology of the day
Do you claim that to distinguish the technology necessary for the two machines?
The example of the machined ball bearing is great!
But both your other examples are false. Ctesibius did not just make a tabletop science demo, but also used steam engines to do useful work, namely opening temple doors. Babbage designed a working computer, which we know because people built it. He correctly computed the necessary tolerances and they were within the tolerances available at the time. The only problem was that he was defrauded on tolerances, a failure of social technology, or perhaps, a success of cartel social technology.
The difference between “fuzzy” and “arbitrary” is fuzzy, but we should prefer one word over the other.
I see many people say that we should have done vaccine challenge trials, that would have been so much quicker. But we did challenge trials. They were “approved” in September and actually begun in February. If you want fast trials, it makes just as much sense to demand that the regulators run regular trials fast. There is much more to gain on that front.
The actual efficacy trials only took about 2 months* that would have been saved by challenge trials. Most of the time was spent not studying vaccines, but waiting for approval to move on to the next step of the trial, just as all a year was spent waiting for approval for challenge trials. The criterion for moving from phase 2 to phase 3 is very simple and should not have taken any time at all, nor any explicit permission. It is perfectly reasonable for regulators to not want to trust the drug companies, but they can check the data after the fact. And if there are analyses that they did not foresee, they can do those after the new trials has already begun.
* The amount of time for efficacy in a non-challenge trial depends on the prevalence of the disease. The actual duration of 2 months was not predicted ahead of time. The FDA’s late addition of 2 months of safety data suggests that it was surprised how fast the efficacy data came in. Also, challenge trials don’t provide safety data, only efficacy. It’s good to separate safety from efficacy and make an explicit decision, a decision that the FDA tried to avoid for half of the trial. When people say that challenge trials save time, they are ignoring this, implicitly endorsing no such medium-term safety data. That’s probably the right choice, but people who make it should say it loud, not dodge responsibility like the FDA.
The Novavax candidate is a recombinant protein.
Here is a specific proposal about the role of sexiness, ie, newness. I don’t mean to put a lot of weight on this hypothesis as opposed to the general class, but it is useful to spell out details. Also, I’m not sure what you’re saying and I suspect this is about a somewhat different irrationality than you were proposing.
Perhaps governments will not allow drug companies to profit in cash from selling vaccines. But they can still profit in intangible experience. This is most obvious with Moderna and BioNTech, whose existence is predicated on mRNA vaccines working in general and the companies being able to make them in particular. After this is over, they may not have any more net cash, but they will find it easier to raise money and convince regulators, not to mention that they will be more competent. Similarly, AZ and J&J will learn about vector vaccines.
I don’t know about subtle difference between proteins and peptides, but I would say the relevant category is “recombinant vaccines” and I believe that the first such was the Hepatitis B vaccine approved in 1986. This used genetically engineered yeast to produce a protein from the virus that was harvested and injected into people.
I often hear people claim that Hong Kong and Singapore are Georgist. More specifically, I hear that they have Land Value Taxes. Their success is often attributed to their Georgism.
Hong Kong has a property tax that is not at all an LVT. Singapore has a tax that it claims is a LVT, but it’s really just a property tax that is reassessed when a new building is proposed, rather than complete. I guess that improves incentives, but it seems pretty minor.
There is more to the spirit and letter of Georgism. The central conceit is state ownership of land, which both cities try to monopolize, offering only 99 year leases. I guess this cuts down on long-term “speculation,” but George’s proposals usually seem focused on a shorter term.
The modern account is to emphasize that the value of cities is the positive externalities from all the development. A government should encourage the production of positive externalities, in particular more building. The cities do take this to heart and make it easy to build. Maybe Georgism is really simple and that’s the key point. So many other cities fail it, but it’s not because of failing to grasp the abstract argument for an LVT or the difficult details of implementing it, but because of much more basic and fundamental failure.
Hypothesis: “Flatten the curve” took off because it allows people to participate without 1. signaling they care what happens to them. 2. think things will get bad or 3. think bad things are preventable.
Georgism
I’m going to write some things about Georgism, prompted by the review of George in the SSC contest. I had a pretty positive view of Georgism before, but had a pretty negative reaction to the review. I have not read George, but it gave me an impression of monomania. It is implausible that land is the root of all evil: of the Irish famine, the 19th century Depression, and modern urban dysfunction. I had first heard of Georgism and LVT for the coordination of modern cities, but I never gave much thought to what it was originally about.
I expect to write a bunch of comments as replies to this comment, which will serve to keep them together. I want multiple comments mainly because I expect to write them on different days and don’t want one to prevent the publication of the other. For good or for ill, this will avoid bridging topics.
That’s a group selection argument.
Although it is widely held by biologists that there is a tradeoff between infectiousness and virulence, people (eg, Paul Ewald) who actually study the evolution of virulence say the opposite, both in theory and data. In the case of sars2, it is overdetermined: death is due to immune overreaction, after the window of selection is over.
Recently I’ve run across several people offhandedly offering disclaimers that they’ve never personally checked that the earth is round. I’ve never thought to check either, but a moment’s reflection reveals that I’ve traveled far enough, both north-south and east-west that the curvature is obvious.
Time zones are a measure of the curvature of the earth. When I travel from New York to California, I know that noon has changed, trusting only my wristwatch. In fact, it was pretty clear to my circadian rhythm. Or just make a phone call to someone you trust on the other coast. Most of the time I don’t discuss sunlight on such calls, but it has come up.
I’ve traveled shorter distances north-south. I’ve been to Glasgow, which is 15 degrees north of NYC. If I went in the spring, there’s probably little to notice, but I went near the solstice, when it was obvious that the nights were much shorter. Similarly, if you go south 15 degrees to Miami, I’m told that the winter and summer day lengths are obviously moderated.
Accurate clocks and instant communication give us a big advantage over the ancients, but the north-south method is largely unchanged.
Added: East-West travel produces a linear effect. North-South travel produces non-linear effects, which can be easy to notice. If I were measuring the height of the sun at noon, that would be linear in the latitude. 15 degrees might be enough to measure without instruments, if I chose to think about it. But the length of the night is not linear. Summer solstice night heads to zero not at the north pole, but just at the arctic circle. So summer solstice in Glasgow was obviously shorter than any night I had previously experienced, maybe cut in half. Whereas summer solstice in Miami is shorter than summer solstice in New York, but just an ordinary length day from other times of the year. Maybe if I had thought to ask the question I could have told the difference without a clock, but I didn’t think about it, whereas the night in Scotland was striking and a topic of conversation. If someone from Miami comes to New York for the solstice, he will experience the shortest night of his life, which might be obvious, but it won’t as dramatic as half the length he’s used to. I knew a guy who moved from Miami to New York and he noticed it, but I think it was about the experience of life, not a single night. There is another non-linear effect as you head to the tropics, which is the solstice shadows at noon shorten to zero. That might be obvious to some people, but it’s not the kind of thing I pay attention to.
All the modeling efforts talked about in the write-up are doomed because they don’t understand the role of the control system
Is that a forward-looking prediction? What consequences was UIUC doomed to? The article ends its coverage of UIUC in early September, declaring it a failure. But, in fact, it achieved its goal of keeping infections below 5k. You could credit that to “the control system,” the panic caused by the early spike that got all the news coverage, but it’s still a success.
If it’s so cheap and easy to make vaccines, why aren’t commercial ones made this way? In particular, the Novavax vaccine sounds similar, so why wasn’t that the first vaccine to market?
Added: Specifically, the ultimate purpose of a vaccine is to get protein into the body. Traditional vaccines grow the virus using its own reproductive apparatus. Fancy new vaccines, like the adenovirus and mRNA vaccines inject instructions and induce the subject to manufacture proteins. But if it’s so easy to just print proteins, why don’t we do that? That’s what Novavax does, unlike the ~7 vaccines that beat it to market.
Added: one difference is that all the vaccines that made it to market, including, I think, Novavax, used the whole spike protein, whereas this proposal uses short peptides. Identifying the right short snippets takes time, while using the whole protein is simpler and more likely to work. The cost of peptides is probably super-linear in length. Still, I remain confused about Novavax.
Your statement last week was correct: there is no known danger of vaccines during pregnancy. There is general advice to avoid them because of purely theoretical dangers.