Berkeley: University of California Press. ISR Center for Political Studies (1973), OSIRIS III: Integrated Collection of Computer Programs for the Management and Analysis of Social Science Ann Arbor, Michigan: University of Michigan Press. Ling, R. F. (1974), Comparison of Several Algorithms for Computing Sample Means and Variances, Journal of the American Statistical Association, 69, 859-66. Longley, J. W. (1967), An Appraisal of Least Squares Programs for the Electronic Computer from the Point of View of the User, Journal of the American Statistical Association, 62,81941. Nie, N. H., Hull, C. H., Jenkins, J. G., Steinbrenner, K., and Bent, D. (1975), SPSS: Statistical Package for the Social Sciences, 2nd ed., New York: McGraw-Hill Book Co. Wampler, R. H. (1970), Report on the Accuracy of Some Widely Used Least Squares Computer Programs, Journal of the American Statistical Association, 65, 549-65. Wilkinson, L. (1975), REGM: A Multivariate General Linear Hypothesis Program for Least Squares Analysis of Multivariate Data, Behavior Research Methods & Instrumentation, 7,485-6.