The ANOVA table decomposes the variance of M into two components: a between-group component and a within-group component. The F-ratio, which in this case equals 64.5336, is a ratio of the between-group estimate to the within-group estimate. Since the P-value of the F-test is less than .05, there is a statistically significant difference between the mean M from one level of TR to another at the 95.0% confidence level. To determine which means are significantly different from which others, select Multiple Range Tests from the list of Tabular Options.