Power or Alpha? The Better Way of Decreasing the False Discovery Rate

The replication crisis in psychology has led to an increased concern regarding the false discovery rate (FDR) – the proportion of false positive findings among all significant findings. In this article, we compare two previously proposed solutions for decreasing the FDR: increasing statistical power and decreasing significance level α. First, we provide an intuitive explanation for α, power, and FDR to improve the understanding of these concepts. Second, we investigate the relationship between α and power. We show that for decreasing FDR, reducing α is more efficient than increasing power. We suggest that researchers interested in reducing the FDR should decrease α rather than increase power. By investigating the relative importance of both α level and power, we connect the literature on these topics and our results have implications for increasing the reproducibility of psychological science.