Why we can’t take expected value estimates literally (even when they’re unbiased)

Holden Karnofsky · 18 Aug 2011 · blog.givewell.org ↗

8 korrents from this piece

Holden Karnofsky did not write this page.

Every claim below was made in this piece, quoted word for word and numbered in the order the piece makes them, so you can read it there rather than take our word for it. The sentence above each quote is our reading of the claim, not their wording. Each quote was checked against a stored copy of the page at build time; where the two differ, the quote is the fact.

Our reading
Give where there is strong evidence that donations do a lot of good, rather than where weak evidence suggests they might do far more.

Their wordsAnd we generally prefer to give where we have strong evidence that donations can do a lot of good rather than where we have weak evidence that donations can do far more good

Interesting
Our reading
A world where altruists followed expected-value estimates would be one where nearly all of them helped distant strangers instead of the people around them, and that world would be worse.

Their wordsIn such a world, it seems that nearly all altruists would put nearly all of their resources toward helping people they knew little about, rather than helping themselves, their families and their communities. I believe that the world would be worse off if people behaved in this way, or at least if they took it to an extreme.

Interesting
Our reading
The moment one cause looks far better than every other on thin information is exactly the moment it most needs sceptical investigation.

Their wordsYet it seems that when people are valuing one action far above others, based on thin information, this is the time when skeptical inquiry is needed most.

Interesting
Our reading
Ranking charities by their estimated expected value alone removes any reward for being transparent about how they actually work.

Their wordsEEV doesn’t seem to allow rewarding charities for transparency or penalizing them for opacity: it simply recommends giving to the charity with the highest estimated expected value, regardless of how well-grounded the estimate is.

Interesting
Our reading
An ungrounded estimate that promises an enormous payoff should be discarded rather than discounted, because the size of the claim is itself the reason to distrust it.

Their wordsAn ungrounded estimate making an extravagant claim ought to be more or less discarded in the face of the “prior distribution” of life experience.

Interesting
Our reading
The more an argument asks you to do, the more evidence you should require before doing it.

Their wordsThe more action is asked of me, the more evidence I require.

Interesting
Our reading
The deeper anyone digs into a charity's cost-effectiveness estimate, the more unwarranted optimism they find, so the right prior on giving is a sceptical one.

Their wordsGiving well seems conceptually quite difficult to me, and it’s been my experience over time that the more we dig on a cost-effectiveness estimate, the more unwarranted optimism we uncover.

Interesting
Our reading
A giving approach that ranks options only by estimated expected value, with no preference for better-grounded estimates, is flawed.

Their wordsI feel that any giving approach that relies only on estimated expected-value – and does not incorporate preferences for better-grounded estimates over shakier estimates – is flawed.

Interesting