Thanks, Michael & Sjir, for writing this exhaustive report! The donation distribution is fascinating, and I loved reading your reasoning about & estimation of quantities I didn't know were important. I'm glad GWWC has such a great giving multiplier!
After reading the summary & skimming the full report & working sheet, I've got three questions:
1. Does the dropping of the top 10 donors influence the decision on which groups to target? I think the reasoning to drop their 27% of donations from the giving multiplier is clear, but it's not obvious to me that they should also be dropped when prioritizing, and I could not find this in the report. (You mention the multiplier is not the only thing that influences which groups to target, of course. To me the overall distribution seems to imply running a top-100 or top-200 survey could be useful in increasing the multiplier somehow, and this argument would be about twice as strong with the top 10 included vs without.)
2. Why did you choose the counterfactual as "what would have happened had GWWC never existed"? I think it's somewhat plausible that the pre-2020 pledgees would still have donated 10% of their income from 2020 onward, had GWWC existed from 2020 onward in a very minimal form. This is about ~35% of the total donations, so this also seems a relevant counterfactual.
3. Similar to 2, I also didn't quite get how you dealt with which GWWC year gets to count the impact from past pledges. It would seem off to me if both GWWC 2020-2022 and GWWC 2017-2019 get to fully count the donations a 2018 pledge-taker made in 2022 for their multipliers, although both of them definitely contributed to the donations, of course. How did you deal with this? Maybe this is addressed by the survey responses already?
A tangentially related point about example 1: Wow, it really surprises me that crypto exposure wasn't hedged!
I can think of a few reasons why those hedges might be practically infeasible (possibilities: financial cost, counterparty risk of crypto hedge, relationship with donor, counterparty risk of donor). I take your point that it'd be appropriate if these sorts of things got discussed more, so I think I will write something on this hedging tomorrow. Thanks for the inspiration!
Thank you for the explanation & references, all three points make sense to me!