“…The frequency distribution of the kinematics data determines the types of statistical analyses that can be validly carried out on the data (Limpert et al, 2001; Limpert and Stahel, 2011). The PD literature often uses ANOVA (analyses of variance) and regression analyses to test a hypothesis see for example (Poizner et al, 1998; Messier et al, 2007; Chan et al, 2010; Mera et al, 2011; Sande De Souza et al, 2011; Venkatakrishnan et al, 2011) just to cite a few. However, these methods require that the data be normally distributed.…”