Program Corfree: A Program for Freeman's Family of Ordinal Correlation Coefficients

Abstract

This paper describes a computer program, CORFREE, which computes the ordinal correlations discussed by Freeman. The correlation coefficients are calculated for the sample data, and the population values are estimated by a combination of the jackknife with robust/resistant methods. The sampling variance of each correlation coefficient is estimated by robust/resistant methods. The program computes one- and two-tailed significance tests of the null hypothesis by randomization methods. The program is useful for calculating the descriptive family of ordinal correlation coefficients described by Freeman, and for finding their significance levels. The program uses computer intensive methods to reduce errors or biases in estimating the population coefficients or their sampling variances. Program outputs can be further analyzed by other programs.