STATOOLS: Statistical Utility Programs

Abstract

STATOOLS is a set of stand-alone programs designed to fill in some of the gaps left by major statistical program packages such as SAS, SPSS-X, BMDP, and SYSTAT. PC-PITMAN, built around a FORTRAN translation of the functions PP1 and PP3 of Streitberg and Rohmel (1984), calculates observed significance levels using recursive relationships to obtain the randomization (permutation) distribution of a number of statistics without directly examining all possible permutations of the data. It performs exact randomization tests (oneand two-sample). It also performs Wilcoxon signed-rank tests and Wilcoxon-Mann-Whitney U tests in the presence of an arbitrary number of ties in the data. The example of 18 observations (5 in one group, 13 in the other) cited by Koslov and Enright (1985) is analyzed in a matter of seconds on an IBM PC with an 8087 coprocessor installed. Data may be entered through the keyboard or from an external file. PC-PITMAN contains 873 lines, 294 of which are comments. PC-MULTI performs multiple comparisons using Tukey's honest significant differences (studentized range statistic). The user enters cell means, number of observations on which each mean is based, an estimate of the error variance, and its degrees of freedom. In the case of unequal cell counts, PC-MULTI performs a Kramer-Tukey analysis. Hayter (1984) proved that this procedure is conservative. Information may be entered through the keyboard or from an external file. Output, which is both numerical and graphical, may be saved in an external file. PC-MULTI contains 603 lines, 195 of which are comments. FORGET-IT produces Forget-it Plots (also known as Two-way Plots), a graphical device described by Tukey (1970; 1977) for displaying the interaction structure of a two-way table. The two-way table of means may be entered through the keyboard or from an external file. The plot, the size of which can be adjusted by the user, may be saved in external file. Only line printer graphics are used. FORGETIT contains 463 lines, 114 of which are comments. PC-EMS produces tables of expected mean squares for balanced experiments using the algorithm of Cornfield and Tukey (1956). Models are entered using standard notation. The user specifies whether each factor is fixed or random. The resulting EMS table may be saved in an external file. PC-EMS contains 293 lines, 102 of which are comments. The programs are written in FORTRAN-77. Diskettes (for the IBM PC and compatibles running DOS 2.0 or later versions) containing the source code, executable files, and user's guides can be obtained by sending a check for $10 to the address below. Please do not send purchase orders.