Effects of Age and Amplitude on performance, for each condition of precision.

Significance threshold is p = .05. The Greenhouse-Geisser corrective coefficient has been applied to the values of p because the distributions are not spherical, according to the Mauchly test. Δ = magnitude of effect determined as the maximal differences between marginal means expressed in percentage of overall Mean (unlike average difference, maximal difference allows comparing magnitude for variables that have different numbers of modalities, 2, 4 and 8).