Predict the More Predictive Test
By Bryan Caplan
IQ scores predict a wide range of life outcomes and respond to incentives. But almost all of the evidence that IQ predicts life outcomes comes from IQ tests that don’t use incentives. Which raises a big question: Would incentivized IQ tests be better or worse predictors of life outcomes than standard IQ tests?
I see arguments on both sides. You could say that…
1. Incentivized IQ tests are cleaner measures of true intellectual ability, and will therefore better predict life outcomes.
2. Life outcomes are incentives, so incentivized IQ tests are more ecologically valid predictors of performance.
3. People respond somewhat myopically to incentives. On this story, the response of IQ scores to incentives will exceed the respond of life outcomes to incentives. Or from a slightly different perspective: Maybe an important cause of life success is the willingness to try when there aren’t blatant incentives to exert yourself. On either story, standard IQ tests will be more predictive of life outcomes.
4. Standard IQ tests measure intelligence and motivation, and are therefore better predictors of life outcomes than incentivized IQ tests, which are closer to pure measures of intelligence.
5. A key ingredient of life success is trying when effort pays and relaxing when effort doesn’t pay. On this story, incentivized IQ tests will be better predictors of life outcomes.
In the end, my intuition is that standard IQ tests will prove to be better predictors of life outcomes than incentivized IQ tests. But I’m far from sure. Your thoughts? Further evidence? Bets?