The selective publishing approach of W&H assumes that each subsequent study in a line of research (i.e., a study on a given topic) involves a test of the null hypothesis that the population effect equals the summary effect obtained by a meta-analysis on the previously published findings (a so-called cumulative meta-analysis). Findings are only published when they are significantly different from the summary effect on the basis of earlier published results (α = .05, two-tailed test). If studies have not yet been published in a research line, the null hypothesis is that there is no effect. W&H's selective publishing has at least three merits. First, the model can explain the Proteus phenomenon reflecting the observation that the first publication on a given topic usually overestimates and the second publication tends to underestimate the effect [1], [22]. Second, W&H show that selective publishing yields an accurate estimate of the population effect already after five or more publications. Third, as a consequence, the selective publishing approach provides a more accurate estimate of the population effect size than an approach wherein each study
