Synthetic recovery
Effect-Size Benchmarks for Education
Kraft (2021) · Education Policy
All five gates passed
Power analysis produces sample sizes consistent with Kraft benchmarks
Description
Validation that the engine’s power analysis produces sample sizes consistent with Kraft’s benchmarks. Kraft argues d = 0.20 is a large effect in field conditions.
Methodology
Simulated 1,000 learners across 25 items and ran the engine’s internal power analysis to determine the minimum sample size needed to detect d = 0.20 at 80% power.
Reference
Kraft, M. A. (2020). Interpreting effect sizes of education interventions. Educational Researcher, 49(4), 241–253.
This is a synthetic recovery, not a replication of the original study. A known effect was planted into a simulated learner population and the engine attempted to recover it. Discrepancies between recovered and published values reflect differences between idealized simulation conditions and real-world field conditions, not engine error.