How would you choose the distributions for the model weights in a way that's not itself arbitrary? E.g. how do you choose their forms and parameters in a way that's not arbitrary?

I do think imprecise credences have a similar problem of deciding which distributions to include in their representor. I think ultimately we need to make some arbitrary choices and should accept some, but we can be more or less arbitrary, or stop when it's no longer decision-relevant. Maybe sometimes we can hit a fixed point or see some kind of convergence in the extra steps we're taking.

On there potentially being no fact of the matter, this may be helpful. It goes further than the issue of imprecise credences/EVs.

On the nematode example, it could go further than that: we might assign an imprecise credence between X and 100% to a set of standards for sentience that nematodes don't meet (see my other post on gradations of moral weight). So, the ratio could be anywhere between 0 and 1 (assuming we're taking the absolute value, or only consider same-sign valence).

If the ratio is anywhere between 0 and 1, then whenever we're looking at affecting nematode-seconds relative to their welfare ranges more than human-seconds relative to our welfare ranges, it would be indeterminate which is affected more. I think that would be every time in practice.

If we don't need to deal with gradations/vagueness like this, then I would probably assign expected welfare ranges (conditional on sentience) between constant and roughly proportional to the number of neurons, and this could give many more practically useful comparisons. EDIT: although conscious subsystems makes me more inclined towards approximately proportional, if we’re entertaining nematode sentience.

Hi Vasco, thanks for the comment and sorry for not seeing this and responding earlier.

I agree that the weights/coefficients in the model could end up quite arbitrary, and I would expect them to if someone tried to set them precisely. My sense is that:

1. We may be able to give some arguments for some bounds on the weights, and some structural constraints on how the weights relate to each other (e.g. it would be odd if we had a function of some measure of complexity like neuron counts that was looked very jagged, but this may be more supported by aesthetics or simplicty than evidence).
2. Within these constraints, the choices are very subjective and highly arbitrary. I think the situation is even worse than with gravity, because there may be no way to gather evidence one way or the other, and there may be no fact of the matter at all.

Mood et al., 2023 had an earlier estimate:

The FAO (2022c) describes a system in which 4,500 hatchling carp are concurrently stocked to feed each mandarin fish. If this is typical then mandarin farming overall consumes an estimated 3,000 billion feed fishes, i.e. 3.0 × 10¹², based on an estimated 674 million mandarin fish (Table 3).

From the FAO source (archived):

According to field practice, live foods should be at a density of 3 800–4 500 fish per m². Moreover, the size of the live food should be well controlled to keep pace with the growth rate of the cultured fish. In order to provide an appropriate quantity of live food, provision procedures are suggested as: 1 to 4 days after pond fertilization, silver carp and bighead carp hatchlings are stocked as live foods at 1 500 per m²; one week later, the same quantity is again stocked; and again an additional week later, stocking of the same number is performed. The third stocking should be accompanied by the stocking of mandarin fish of size 3–4 cm at an average rate of 1 fish per m².

So 1 mandarin fish per m² vs 3 800–4 500 feed fish per m²?

Why do you think it was naive instead of a good bet that happened to not work out?

Another two:

1. Rethink Priorities, but could be hard to evaluate. You'd also have to restrict funding to the animal department.
2. THL UK, which fundraises separately from THL and gets limited funding from THL.

I had Perplexity do a review and compare PETA's report with Welfare Footprint's research here, and also critique and review the report Perplexity generated here. Summary from the second link:

Where Models Agree

Another: Animal Policy International

I'm guessing this is on your radar, but I think it's worth checking basically every Coefficient Giving, Navigation Fund and EA Animal Welfare Fund grantee over the last ~2 years.

You could focus on those that received at least $X (e.g. $100K) if you're looking to filter quickly, but we should also be looking to get good orgs to consider more ambitious plans.