A MACINTOSH BASIC PROGRAM FOR FITTING LINEAR ADDITIVE-MODELS TO DATA BY WEIGHTED LEAST-SQUARES METHODS, WITH AUTOMATIC ELIMINATION OF REDUNDANT PARAMETERS FROM THE MODEL

A BASIC program for fitting linear additive models to data with weight ed or unweighted least squares methods and matrix procedures is descri bed. Written and compiled to run on Macintosh II type machines (68020/ 68030/68040) with coprocessor (68881/68882), the program fits the mode l supplied by the user as an X or design matrix and provides the optio n of making the model's parameters orthogonal. Predicted values plus r egression and residual terms are calculated. For the weighted fit, the significance of the residual term is evaluated and redundant paramete rs sequentially and automatically removed until a minimum adequate mod el is achieved. An appropriate design matrix allows weighted fitting o f models for multiway analyses of variance (e.g. factorial, nested and split plot), simple or multiple linear or curvilinear regression, com binations of these in covariance analyses, and genetic analyses (inclu ding diallel cross analyses). Sums of squares for individual parameter s and orthogonal comparisons can be calculated by the program.