Translating Standardized Effects of Education Programs Into More Interpretable Metrics

Abstract

Evaluators report effects of education initiatives as standardized effect sizes, a scale that has merits but obscures interpretation of the effects’ practical importance. Consequently, educators and policymakers seek more readily interpretable translations of evaluation results. One popular metric is the number of years of learning necessary to induce the effect. We compare years of learning to three other translation options: benchmarking against other effect sizes, converting to percentile growth, and estimating the probability of scoring above a proficiency threshold. After enumerating the desirable properties of translations, we examine each option’s strengths and weaknesses. We conclude that years of learning performs worst, and percentile gains performs best, making it our recommended choice for more interpretable translations of standardized effects.