Exogenous Failure Assignment

In Simple Words

Imagine testing how drivers handle an unexpected patch of black ice on a road. If drivers only go onto the icy road voluntarily, only risk-tolerant drivers are tested; but if a road detour forces a random selection of drivers onto the ice patch, researchers can measure true handling ability and recovery without selection bias.

Research question

In observational settings, analyzing how individuals respond to negative performance feedback is confounded by self-selection, as individuals who voluntarily choose difficult tasks differ systematically from those who select easy tasks.

Participants

N = 1,491 elementary school students forced into the difficult task in Round 1 (Sample A: N = 817; Sample B: N = 674) in Istanbul, Turkey.

Study Design

Randomized assignment implemented via a 50% chance of forced execution in Round 1 to break self-selection into task difficulty.

Results

Among the subset forced into the difficult task who failed in Round 1 (N = 558 in Sample A, N = 522 in Sample B), treated students re-attempted the difficult task in Round 2 at rates 17.6 percentage points higher in Sample A (p = 0.002) and 13.9 percentage points higher in Sample B (p = 0.064) than control group baseline rates of 36% and 51%.

Takeaway

Implement forced probabilistic assignment to challenging condition rounds in experimental trials to evaluate post-failure persistence free of selection bias.

Read alongside the research

Plain-English glossary

Original explanations, informed by the references below. Examples are illustrations, not data from the studies above. The research text stays unchanged.

Percentage points

The difference between two percentages.

ExampleA rise from 40% to 50% is 10 percentage points. Relative to the starting value, that is a 25% increase.

Office for National Statistics · Percentages ↗Read more about percentage points →

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