Power analysis for a step potential. Minimum Ct(A) and (B) that allows rejecting H0: "no interaction" (α = 0.05) as a function of the base-level . In A, the expected value of Ctunder H0 is indicated by a dashed line. (C) Statistical power (1 - β) for detecting interactions of a true strength ϵ = 1. Red, green, and blue lines correspond to N = 10, 100, and 1000, respectively, in all three panels.