Estimating the reproducibility of psychological science¶
Why this mattered¶
TBD
Abstract¶
Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams.
Related¶
- cite → Why Most Published Research Findings Are False — The reproducibility project tests Ioannidis's claim that low power, bias, and multiple testing make many published findings false.
- cite → False-Positive Psychology — The reproducibility project cites false-positive psychology as evidence that researcher degrees of freedom can inflate statistically significant effects.
- enables ← Why Most Published Research Findings Are False — Ioannidis's false-findings argument enabled the Reproducibility Project by motivating large-scale empirical tests of published psychological results.