Abstract: |
Equivalence testing methods can provide statistically significant evidence
that relationships are practically equal to zero. I demonstrate their
necessity in a systematic reproduction of estimates defending 135 null claims
made in 81 articles from top economics journals. 37-63% of these estimates
cannot be significantly bounded beneath benchmark effect sizes. Though
prediction platform data reveals that researchers find these equivalence
testing 'failure rates' to be unacceptable, researchers actually expect
unacceptably high failure rates, accurately predicting that failure rates
exceed acceptable thresholds by around 23 percentage points. To obtain failure
rates that researchers deem acceptable, one must contend that nearly half of
published effect sizes in economics are practically equivalent to zero.
Because such a claim is ludicrous, Type II error rates are likely quite high
throughout economics. This paper provides economists with empirical
justification, guidelines, and commands in Stata and R for conducting credible
equivalence testing in future research. |