Thanks for the relevant comment, Nick. I strongly upvoted it because I felt it was useful for me to think about this more.
I recommend funding A over B if I think funding A increases welfare more cost-effectively at the margin than funding B (in expectation). However, my numerical estimates of the cost-effectiveness do not integrate all the information I have. If my numerical estimates for the cost-effectiveness of 2 interventions are similar, other factors could easily be decisive.
I agree it would not make sense for a whole community to switch back and forth between 2 interventions with similar positive cost-effectiveness at the margin. The amount of resources moving from the most to the least cost-effective intervention at the margin should tend to 0 as the difference between the marginal cost-effectiveness of the interventions tends to 0.
I also agree it would not make for a single person to be constantly switching back and forth between 2 interventions with similar positive cost-effectiveness at the margin. Spending 1 year to switch to a career path which is 0.1 % more impactful per year, accounting for impact through work and donations, would only make sense if one could work for longer than 1 k years (= 1/ā10^-3) in the new path. This is way too long, and therefore the change would not be worth it.
However, I think the situation is different in the context of constantly switching back and forth between supporting or not an intervention due to large uncertainty about whether it increases or decreases welfare (in expectation). Constant switching leads to spending resources without achieving nothing, which is worse than supporting positive interventions. However, it is unclear whether achieving nothing is better or worse than supporting an intervention which can easily have a positive or negative cost-effectiveness.
In cases where there is large uncertainty about whether an intervention increases or decreases welfare (in expectation), I believe it is often better to support interventions decreasing that uncertainty. This is a major reason for my top recommendation of decreasing the uncertainty about whether soil nematodes have positive or negative lives, which I consider robustly better than constant switching. As I say in the summary, āI am arguing for, by increasing cost-effectiveness, changes in food consumption which increase agricultural land, the most cost-effective global health interventions, and targeted research on whether soil animals have positive or negative livesā.
Thanks for the relevant comment, Nick. I strongly upvoted it because I felt it was useful for me to think about this more.
I recommend funding A over B if I think funding A increases welfare more cost-effectively at the margin than funding B (in expectation). However, my numerical estimates of the cost-effectiveness do not integrate all the information I have. If my numerical estimates for the cost-effectiveness of 2 interventions are similar, other factors could easily be decisive.
I agree it would not make sense for a whole community to switch back and forth between 2 interventions with similar positive cost-effectiveness at the margin. The amount of resources moving from the most to the least cost-effective intervention at the margin should tend to 0 as the difference between the marginal cost-effectiveness of the interventions tends to 0.
I also agree it would not make for a single person to be constantly switching back and forth between 2 interventions with similar positive cost-effectiveness at the margin. Spending 1 year to switch to a career path which is 0.1 % more impactful per year, accounting for impact through work and donations, would only make sense if one could work for longer than 1 k years (= 1/ā10^-3) in the new path. This is way too long, and therefore the change would not be worth it.
However, I think the situation is different in the context of constantly switching back and forth between supporting or not an intervention due to large uncertainty about whether it increases or decreases welfare (in expectation). Constant switching leads to spending resources without achieving nothing, which is worse than supporting positive interventions. However, it is unclear whether achieving nothing is better or worse than supporting an intervention which can easily have a positive or negative cost-effectiveness.
In cases where there is large uncertainty about whether an intervention increases or decreases welfare (in expectation), I believe it is often better to support interventions decreasing that uncertainty. This is a major reason for my top recommendation of decreasing the uncertainty about whether soil nematodes have positive or negative lives, which I consider robustly better than constant switching. As I say in the summary, āI am arguing for, by increasing cost-effectiveness, changes in food consumption which increase agricultural land, the most cost-effective global health interventions, and targeted research on whether soil animals have positive or negative livesā.