Tables for cumulative probability of the ex-Gaussian distribution
The ex-Gaussian distribution provides a good fit to multiple empirical positive skewed distributions, such as reaction time. This fit is a useful tool when estimating confidence intervals and determining hypothesis testing for skewed variables. In order to create tables for significance testing, the ex-Gaussian distribution was parametrize in terms of its average, standard deviation and a new skewness parameter λ = ∛(t/2). To this end, x was standardized in order to normalize the ex-Gaussian distribution for average of 0 and standard deviation of 1. In this way, the distribution has only one free parameter (0 ≤ λ < 1).
Keywords: ex-Gaussian distribution, significance testing, statistical tables.