I think maybe I was confused about what you are saying. You said:
I think this applies to growth in local groups particularly well… While I’ve no doubt that many of the groups that have been founded by people who joined since 2015*, I suspect that even if we cut those people out of the data, we’d still see an increase in the number of local groups over that time frame- so we can’t infer that EA is continuing to grow based on increase in local group numbers.
But then also:
Fwiw, this seems like more direct evidence of growth in EA since 2015 than any of the other metrics
In my mind, A being evidence of B means that you can (at least partially) infer B from A. But I’m guessing you mean “infer” to be something like “prove”, and I agree the evidence isn’t that strong.
DM: While I’ve no doubt that many of the groups that have been founded by people who joined since 2015*, I suspect that even if we cut those people out of the data, we’d still see an increase in the number of local groups over that time frame- so we can’t infer that EA is continuing to grow based on increase in local group numbers.
BW: It sounds like maybe when you say “we can’t infer that EA is continuing to grow based on increase in local group numbers” you mean “part of the growth might be explained by things other than what would be measured by a change in number of groups”? (Or possibly “increasing group numbers is evidence of growth since 2015, but not necessarily evidence of growth since, say, 2019”?)
I meant something closer to: ‘we can’t infer Y from X, because we’d still expect to observe X even if ¬Y.’
My impression is still that we have been somewhat talking past each other, in the way I described in the second paragraph of my previous comment. My core claim is that we should not look at the number of new EA groups as a proxy for growth in EA, since many new groups will just be a delayed result of earlier growth in EA, (as it happens I agree that EA has grown since 2015, but we’d see many new EA groups even if it hadn’t). Whereas, if I understand it, your claim seems to be that as we know that at least some of the new groups were founded by new people to EA, we know that there has been some new EA growth.
I think maybe I was confused about what you are saying. You said:
But then also:
In my mind, A being evidence of B means that you can (at least partially) infer B from A. But I’m guessing you mean “infer” to be something like “prove”, and I agree the evidence isn’t that strong.
I meant something closer to: ‘we can’t infer Y from X, because we’d still expect to observe X even if ¬Y.’
My impression is still that we have been somewhat talking past each other, in the way I described in the second paragraph of my previous comment. My core claim is that we should not look at the number of new EA groups as a proxy for growth in EA, since many new groups will just be a delayed result of earlier growth in EA, (as it happens I agree that EA has grown since 2015, but we’d see many new EA groups even if it hadn’t). Whereas, if I understand it, your claim seems to be that as we know that at least some of the new groups were founded by new people to EA, we know that there has been some new EA growth.