Short version: I want to discourage people from using these numbers in any context where that level of precision might be relevant. That is, if the sign of someone’s analysis turns on three significant digits, then I doubt that their analysis is action-relevant.
As for medians rather than means, our main concern there was just that means tend to be skewed toward extremes. But we can generate the means if it’s important!
Finally, I should stress that I’m seeing people use these “moral weights” roughly as follows: “100 humans = ~33 chickens (100*.332= ~33).” This is not the way they’re intended to be used. Minimally, they should be adjusted by lifespan and average welfare levels, as they are estimates of welfare ranges rather than all-things-considered estimates of the strength of our moral reasons to benefit members of one species rather than another.
As for medians rather than means, our main concern there was just that means tend to be skewed toward extremes. But we can generate the means if it’s important!
Do you think the extremes of your moral weight distributions are reasonable? If so, even if the mean is skewed towards them, it would become more accurate. Anyways, I would say sharing the mean would be important, such that people could see how much influence extremes have (i.e. how heavy-tailed is the moral weight distribution).
Sorry for the slow reply, Vasco. Here are the means you requested. My vote is that if people are looking for placeholder moral weights, they should use our 50th-pct numbers, but I don’t have very strong feelings on that. And I know you know this, but I do want to stress for any other readers that these numbers are not “moral weights” as that term is often used in EA. Many EAs want one number per species that captures the overall strength of their moral reason to help members of that species relative to all others, accounting for moral uncertainty and a million other things. We aren’t offering that. The right interpretation of these numbers is given in the main post as well as in our Intro to the MWP.
Thanks for clarifying and sharing the means, Bob! There are some significant differences to the medians for some species, so it looks like it would be important to see whether the extremes of the distributions are being well represented.
Short version: I want to discourage people from using these numbers in any context where that level of precision might be relevant.
I thought this would be the reason. That being said, I still think it makes sense to present the results with 2 or 3 significantdigits whenever the uncertainty is already being conveyed. For example, if I say the mean moral weight is 1.00, and the 5th and 95th percentiles are 0.00100 and 1.00 k, it should be clear that the result is pretty uncertain, even though all numbers have 3 significant digits.
That is, if the sign of someone’s analysis turns on three significant digits, then I doubt that their analysis is action-relevant.
I agree in general, but wonder whether for some cases it may matter in a non-crucial way. For example, the ratio between 1.50 and 2.49 is 0.602 without rounding, but 1 if we round both numbers to 2. An error of a factor of 0.602 may not be crucial, but it will not necessarily be totally negligible either.
Finally, I should stress that I’m seeing people use these “moral weights” roughly as follows: “100 humans = ~33 chickens (100*.332= ~33).” This is not the way they’re intended to be used.
Ahah, I agree! They are supposed to be used as follows: “100 chickens = 100*0.332 humans = 33.2 humans”. One should always be careful not to interpret the moral weight of chickens relative to humans as that of humans relative to chickens, and also present the final result with 3 significant digits instead of 2.
Jokes apart, when I read “[based on RP’s median moral weights] 100 chickens = 33.2 humans”, I assume we are considering the duration and intensity of experience (relative to the moral weight) are the same for both humans and chickens, because that is what the moral weight alone tells us. However, if one says “saving x humans equals saving y chickens”, I agree the moral weights have to be combined with other variables, because now we are describing the consequences of actions instead of just a direct comparison of experiences.
Thanks, Vasco!
Short version: I want to discourage people from using these numbers in any context where that level of precision might be relevant. That is, if the sign of someone’s analysis turns on three significant digits, then I doubt that their analysis is action-relevant.
As for medians rather than means, our main concern there was just that means tend to be skewed toward extremes. But we can generate the means if it’s important!
Finally, I should stress that I’m seeing people use these “moral weights” roughly as follows: “100 humans = ~33 chickens (100*.332= ~33).” This is not the way they’re intended to be used. Minimally, they should be adjusted by lifespan and average welfare levels, as they are estimates of welfare ranges rather than all-things-considered estimates of the strength of our moral reasons to benefit members of one species rather than another.
Hi again,
Sorry, I forgot to touch on this point:
Do you think the extremes of your moral weight distributions are reasonable? If so, even if the mean is skewed towards them, it would become more accurate. Anyways, I would say sharing the mean would be important, such that people could see how much influence extremes have (i.e. how heavy-tailed is the moral weight distribution).
Sorry for the slow reply, Vasco. Here are the means you requested. My vote is that if people are looking for placeholder moral weights, they should use our 50th-pct numbers, but I don’t have very strong feelings on that. And I know you know this, but I do want to stress for any other readers that these numbers are not “moral weights” as that term is often used in EA. Many EAs want one number per species that captures the overall strength of their moral reason to help members of that species relative to all others, accounting for moral uncertainty and a million other things. We aren’t offering that. The right interpretation of these numbers is given in the main post as well as in our Intro to the MWP.
Thanks for clarifying and sharing the means, Bob! There are some significant differences to the medians for some species, so it looks like it would be important to see whether the extremes of the distributions are being well represented.
Thanks for clarifying!
I thought this would be the reason. That being said, I still think it makes sense to present the results with 2 or 3 significantdigits whenever the uncertainty is already being conveyed. For example, if I say the mean moral weight is 1.00, and the 5th and 95th percentiles are 0.00100 and 1.00 k, it should be clear that the result is pretty uncertain, even though all numbers have 3 significant digits.
I agree in general, but wonder whether for some cases it may matter in a non-crucial way. For example, the ratio between 1.50 and 2.49 is 0.602 without rounding, but 1 if we round both numbers to 2. An error of a factor of 0.602 may not be crucial, but it will not necessarily be totally negligible either.
Ahah, I agree! They are supposed to be used as follows: “100 chickens = 100*0.332 humans = 33.2 humans”. One should always be careful not to interpret the moral weight of chickens relative to humans as that of humans relative to chickens, and also present the final result with 3 significant digits instead of 2.
Jokes apart, when I read “[based on RP’s median moral weights] 100 chickens = 33.2 humans”, I assume we are considering the duration and intensity of experience (relative to the moral weight) are the same for both humans and chickens, because that is what the moral weight alone tells us. However, if one says “saving x humans equals saving y chickens”, I agree the moral weights have to be combined with other variables, because now we are describing the consequences of actions instead of just a direct comparison of experiences.