We've haven't explicitly modeled diminishing returns in this way. Most of the opportunities we consider are for specific pre-defined gaps, so they're more discrete than something you can really scale in that continuous type of way.
We don't select/structure our grants such that we necessarily think the "last dollar" or marginal dollar to that grant is 10x cash. For example: if there was a discrete $5M funding opportunity to support a program in a specific area, we might model the cost-effectiveness of that opportunity as say, 15x overall, but there wouldn't be any particular reason to think the 'last dollar' was more like 10x. Generally, when it comes to funding discrete opportunities (e.g. vaccination promotion in a certain state in Nigeria), we don't tend to think about the value of the first versus last dollar for that discrete opportunity, because we're often making a binary decision about whether to support the program in that area at all. Hope this clarifies!
Thanks to Vasco for reaching out to ask whether GiveWell has considered:
GiveWell has not looked into any of these three areas. We'd likely expect both the costs and the benefits to be fairly specific to the particular context and intervention. For example, rather than estimating the impact of reduced tariffs broadly, we'd ask something along the lines of: What is the intervention that can actually e.g., lead to a reduction in tariffs? On which set of goods/services would it apply? Which sets of producers would benefit from those lower tariffs? And thus, what is the impact in terms of increased income/consumption?
We think there's a decent chance that different methodologies between Copenhagen Consensus Center and GiveWell would lead to meaningfully different bottom line estimates, based on past experience with creating our own estimates vs. looking at other published estimates, although we can't say for sure without having done the work.
Thanks SoGive for the post! We wanted to share some of GiveWell's current thinking around malaria vaccines in case it's helpful. We also wrote a report on RTS,S in 2022 here and have recommended a couple grants for vaccine rollout and research.
On a cost-per-person-reached basis, we agree ITNs and SMC are superior to either of the two WHO-approved malaria vaccines. However, we think there's less of a differential in cost-effectiveness than this post implies, for a number of reasons:
There are, of course, additional factors that need to be taken into account to get a full picture (for example, what coverage levels are achievable for each intervention?). However, our current best guess is that even with those included, nets (and SMC) will be more cost-effective than malaria vaccines - just not by an order of magnitude.
Costs per child reached are much higher, roughly $15-$26.
The price per dose of RTS,S was $9.30 in 2022, and estimates for R21 indicate a price per dose of $3.90. We expect that, on average, 70% of children who received three doses will also get a booster shot, which implies vaccine costs per child between $14-$37. The best costing estimates for the delivery of the doses suggest around $9 per child.
“The leading malaria vaccine in development is the circumsporozoite protein (CSP)-based particle vaccine, RTS,S, which targets the pre-erythrocytic stage of Plasmodium falciparum infection. It induces modest levels of protective efficacy, thought to be mediated primarily by CSP-specific antibodies. We aimed to enhance vaccine efficacy by generating a more immunogenic CSP-based particle vaccine and therefore developed a next-generation RTS,S-like vaccine, called R21. The major improvement is that in contrast to RTS,S, R21 particles are formed from a single CSP-hepatitis B surface antigen (HBsAg) fusion protein, and this leads to a vaccine composed of a much higher proportion of CSP than in RTS,S.” Collins et al. 2017, “Abstract”
Thanks for your comment! To clarify, our funding bar being 10x cash doesn't mean that every grant we make will be to things that are 10x cash – it means that we'll generally fund all of the programs we find that are above 10x, and not the ones that we estimate to be below 10x (with caveats that sometimes we will/won't make grants that fall on either side of that line for other reasons not captured in the CEA, e.g. learning value). You can read more on how we make funding decisions here.
Many of the grants we make are above 10x, including a fair amount in the 10-20x range (like this recent CHAI grant – we estimate delivering the program is ~17x cash, not counting the evaluation grants). Using Against Malaria Foundation (AMF) as an example, we fund net distribution campaigns in specific geographic regions that meet our 10x bar (see this grant made to AMF in January 2022 that supports net distribution campaigns in three Nigerian states). Theoretically, if we evaluated six states for net distribution campaigns and only four states met our criteria to be above 10x, we would only fund those four and not the other two, and the average cost-effectiveness across those 4 states would be higher than 10x.
Hi Sanjay - thanks for the close read! You're right that Figure 3 should read 95%, not 90% - we're working on correcting the figure and will update the post ASAP. Thanks again!
Hi there - thanks so much for catching this! Our malnutrition CEA is not yet public because it's still a work-in-progress. I've removed the hyperlink accordingly. Thanks again!
Hi Vasco and Caleb, we appreciate the interest in the Global Health and Development Fund! This is Isabel Arjmand responding on behalf of GiveWell.
We're grateful for the opportunity to manage this fund, and we think it's a great opportunity for donors who want to support highly cost-effective global health and development programs. We're also interested in having more in-depth conversations with Caleb and others involved in EA Funds about what the future of this fund should look like, and we’ll reach out to schedule that.
In the meantime, here are some notes on our grantmaking and how donations to the fund are currently used.
This is Isabel Arjmand from GiveWell. Thanks for the question!
We continue to recommend both the Against Malaria Foundation and Malaria Consortium's seasonal malaria chemoprevention (SMC) program as top charities (https://www.givewell.org/charities/top-charities). We're also looking at other ways to reduce the burden of malaria, and are supporting programs like vaccine rollouts where we see promising opportunities (e.g. these two grants: https://www.givewell.org/research/grants/PATH-malaria-vaccines-January-2022, https://www.givewell.org/research/grants/PATH-perennial-malaria-chemoprevention-rtss-malaria-vaccine-study-february-2023).
We’ve seen the NYT coverage and are following the relevant issues it covers (e.g. insecticide resistance, for which we include an adjustment in our modeling). We wrote a bit about the news coverage here (https://twitter.com/GiveWell/status/1709634481047425423). The bottom line is that we continue to think the Against Malaria Foundation and Malaria Consortium’s SMC program are great opportunities for donors.
Thank you so much for this thoughtful review!
We've looked through the issues you identify as errors, and we believe that each of those is either not an error or is something we've deprioritized because addressing it would not change our grantmaking decisions. You can see our analysis here.
This only applies to the potential errors you pointed out, not your higher-level feedback or judgment calls. We're grateful for your engagement here, and we are working on improving the architecture of our CEAs, in line with your higher-level feedback. We also recognize that the interpretability of our cost-effectiveness analysis is an area we need to improve, and we're working on that as well.
Since the linked document was written for internal use, it hasn't been fully vetted in the same way that what we publish on our website is. However, we thought it may be useful to share in its current form.