ChaLeT: determining the chance level in perception experiments by menas of binomial test

Abstract

This paper presents ChaLeT, an R script that can be used to determine statistically whether answers given by listeners in a perception test are above chance level. The script has been designed for perception tests where listeners have to choose between two categories. The script makes use of the binomial test of statistical significance to determine the chance level. It then plots the results of the perception test on a chart where coloured ribbons signal the interval where answers are below the chance level.