Giving Compass' Take:

• In this 80,000 Hours podcast, GiveWell researcher James Snowden discusses the dilemmas global health influencers face when evaluating charities and policies that affect different age groups: Whom do we prioritize?

• It may sound cold to look at calculations such as "health-adjusted life-years," but these can often be crucial to determining which organizations are most effective. We shouldn't neglect the human element, though.

• Learn how we can optimize on the edges of global health.

What’s the value of preventing the death of a 5-year-old child, compared to a 20-year-old, or an 80-year-old?

The global health community has generally regarded the value as proportional to the number of health-adjusted life-years the person has remaining — but GiveWell, one of the world’s foremost charity evaluators, no longer uses that approach. They found that contrary to the years-remaining’ method, many of their staff actually value preventing the death of an adult more than preventing the death of a young child. But there’s plenty of disagreement, with the team’s estimates spanning a four-fold range.

As James Snowden — a research consultant at GiveWell — explains in this episode, there’s no way around making these controversial judgement calls based on limited information. If you try to ignore a question like this, you just implicitly take an unreflective stance on it instead. And for each charity they investigate there’s 1 or 2 dozen of these highly uncertain parameters that need to be estimated.

GiveWell has been working to find the best way to make these decisions since its inception in 2007. Lives hang in the balance, so they want their staff to say what they really believe and bring whatever private knowledge they have to the table, rather than just defer to their managers, or an imaginary consensus.

Their strategy is to have a massive spreadsheet that lists dozens of things they need to know, and to ask every staff member to give a figure and justification. Then once a year, the GiveWell team gets together to identify what they really disagree about and think through what evidence it would take to change their minds.

Listen to the full podcast about estimating the unknowable in charity by Robert Wiblin at 80000 Hours.