We do have some evidence about which world we’re in. There are studies which find pretty big differences in level of antibody titer produced by the vaccinated, and in some cases where they have almost no antibodies it’s pretty clear that this means immune responsiveness is going to be at fault when they get sick. And I think there are studies finding correlation between titer and effectiveness. Both of these point toward innateness. But we also know that it has to be true that for many of those with low levels of antibodies, a larger dose will push them over the edge. There is also slight evidence from the Israel numbers, which give effectivenesses that vary some over time, that there’s a serious behavioral/environmental component.
So, we’re in both worlds. VE is a function both of immune response and viral load exposure. Which one is relatively dominant may be important for behavioral implications (I agree with you!), but this doesn’t have to be an either or. “Breakthrough” cases can have multiple input factors. Even the “innate” world comes with the question of whether the vaccine stochastically increases titers across the board or stochastically increases titers only among a susceptible type of person (is it a single distribution or a mixture distribution?). But once we think we’re living in a world where both matter (actually, I wonder to what extent this community endorses this POV or if generally LW thinks it is an either or situation?), and once we obtain a ton more info, the behavioral recommendations can be either really complicated and theoretically optimal but impossible to follow, or they can be simpler and sub-optimal but implementable. We see this with vaccinateds masking—the distribution of titers pretty much indicates vaccinateds will take care of wild type just fine, so the CDC cuts the mask recommendations (despite there being some variation). The titers vs. Delta are not quite so great, so the CDC re-implements the mask recommendations (despite there being some variation). The world is messy.
Yeah sorry, I meant “where on this axis” are we—I had meant the evidence to show “we’re not in one or the other”, but I’ll edit for clarity. (And obviously it’s much more complicated than just this axis, as you point out. I was just trying to make it understandable.)
I agree with the recommendations having the possibility to be complicated+optimal XOR implementable and think it’s an important and somewhat underappreciated point. It makes it somewhat more complicated to give policy recs to family/friends but I’m glad I’m slowly learning how to give rules that are more implementable.
So, we’re in both worlds. VE is a function both of immune response and viral load exposure. Which one is relatively dominant may be important for behavioral implications (I agree with you!), but this doesn’t have to be an either or. “Breakthrough” cases can have multiple input factors. Even the “innate” world comes with the question of whether the vaccine stochastically increases titers across the board or stochastically increases titers only among a susceptible type of person (is it a single distribution or a mixture distribution?). But once we think we’re living in a world where both matter (actually, I wonder to what extent this community endorses this POV or if generally LW thinks it is an either or situation?), and once we obtain a ton more info, the behavioral recommendations can be either really complicated and theoretically optimal but impossible to follow, or they can be simpler and sub-optimal but implementable. We see this with vaccinateds masking—the distribution of titers pretty much indicates vaccinateds will take care of wild type just fine, so the CDC cuts the mask recommendations (despite there being some variation). The titers vs. Delta are not quite so great, so the CDC re-implements the mask recommendations (despite there being some variation). The world is messy.
Yeah sorry, I meant “where on this axis” are we—I had meant the evidence to show “we’re not in one or the other”, but I’ll edit for clarity. (And obviously it’s much more complicated than just this axis, as you point out. I was just trying to make it understandable.)
I agree with the recommendations having the possibility to be complicated+optimal XOR implementable and think it’s an important and somewhat underappreciated point. It makes it somewhat more complicated to give policy recs to family/friends but I’m glad I’m slowly learning how to give rules that are more implementable.