Tables for cumulative probability of the ex-Gaussian distribution

  • Carmen Moret-Tatay Facultad de Psicología, Magisterio y Ciencias de la Educación. Universidad Católica de Valencia San Vicente Mártir.
  • Daniel Gamermann Departamento de Física. Universidade Federal do Rio Grande do Sul.
  • Pedro Fernández de Córdoba Departamento de Matemática Aplicada. Universitat Politécnica de València.
Keywords: ex-Gaussian distribution, significance testing, statistical tables.

Abstract

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.

Published
2018-05-22