abstract:In statistics, polychoric correlation is a technique for estimating the correlation between two theorised normally distributed continuous latent variables, from two observed ordinal variables. Tetrachoric correlation is a special case of the polychoric correlation applicable when both observed variables are dichotomous.
The current paper employed polychoriccorrelation coefficient to analyzeteachingevaluationdata, which has been proved robustand will offer more preciseestimate.