The equality of several means may be tested by the F-test in one-way analysis of variance with or without assuming equal group variances. Both tests are automatically produced. An example of the definitions in the ANOVA operation: ANOVA IEADATA,30 DEPENDENT=KNOWLDGE GROUPING=ATTITUDE ATTITUDE=1(Best),2(Same),3(Worst) METHOD=ONEWAY Multiple comparisons of means may be performed either by using comparisonwise (t tests) or experimentwise significance levels. The names of selected methods are given by the parameter METHOD: TTESTS pairwise t-tests both for equal and unequal group variances. TUKEY Tukey's (equal sample sizes) or Tukey-Kramer's (unequal sample sizes) method. Equal population variances assumed. The latter method can be used only in pairwise mean comparisons. T3 T3 method for both equal and unequal group variances. Pairwise mean comparisons only. BF Brown and Forsythe's method for both equal and unequal group variances. Pairwise mean comparisons as well general contrasts of means. SCHEFFE Scheffe's method for equal group variances. Pairwise mean comparisons and general contrasts of means. GABRIEL Gabriel's approximative method for equal group variances. Usage as Scheffe's method. NK Newman-Keul's procedure, the desired significance level must be given as the option, equal sample sizes only, only significance tests. TWELSCH Newman-Keul's or Dunacn's procedure with Tukey-Welsch specification, the significance level must be given, only significance tests. If the letter S is given in parenthesis after the name of the method e.g. TUKEY(S) then the p-values corresp. to the test statistics are given too. Instead of significance tests you may ask for simultaneous confidence intervals by giving the wanted significance level in parenthesis, e.g. TUKEY(0.05). For t-tests (parameter TTESTS) no confidence intervals may be produced. If only pairwise mean comparisons are wanted then the form of contrasts need not be defined. Otherwise the form of contrasts must be specified by the parameters PAIRWISE, CLEVEL, FGROUP and SGROUP (Not available for NK and TWELSCH): CLEVEL If CLEVEL=i is specified then contrasts of means of the form (1,k-1,0), ..., (i,k-i,0) will be tested, where k is the total number of group means (k>i). Notation (i,k-i,0) refer to those comparisons where the mean of i group means is compared with the mean of other k-i means and no group is ignored. FGROUP Testing a contrasts specified by FGROUP and SGROUP. With para- SGROUP meter FGROUP the group values/labels of the first set of group means are given. The second set is specified by SGROUP. Groups not specified by the parameters FGROUP and SGROUP are ignored. PAIRWISE If both pairwise and more general contrasts are to be tested then specify PAIRWISE=1. Further information: 1 = More on the definitions of the grouping structure M = Multivariate multiple comparisons A = More on ANOVA operations