Simulation settings and additional results.

Recently, novel biotechnologies to quantify RNA modifications became an increasingly popular choice for researchers who study epitranscriptome. When studying RNA methylations such as N6-methyladenosine (m 6 A), researchers need to make several decisions in its experimental design, especially the sample size and a proper statistical power. Due to the complexity and high-throughput nature of m 6 A sequencing measurements, methods for power calculation and study design are still currently unavailable. In this work, we propose a statistical power assessment tool, magpie , for power calculation and experimental design for epitranscriptome studies using m 6 A sequencing data. Our simulation-based power assessment tool will borrow information from real pilot data, and inspect various influential factors including sample size, sequencing depth, effect size, and basal expression ranges. We integrate two modules in magpie : (i) a flexible and realistic simulator module to synthesize m 6 A sequencing data based on real data; and (ii) a power assessment module to examine a set of comprehensive evaluation metrics.