Chapter 9, Table 11: Analyzing Randomized Block Design via SPSS Syntax

The question of interest in the present situation assumes that there are three blocks of elderly participants, six per block. The elderly participants are sorted into the three blocks as a function of their age. The purpose of the study was to assess the effect of age on motor control, measured by the number of errors on a certain task (where there were three tasks). The goal here is to replicate the results from the top portion of Table 9.12 (At this point performing the ANOVA and the ANCOVA also included in Table 9.12 should be straightforward.).

The results given in the upper portion of Table 9.12 can be obtained by making use of the SPSS Univariate ANOVA procedure (UNIANOVA). Because the task and the blocks are both treated as different factors, the analysis proceeds as a two factor design that includes the interaction.

At this point clicking Run and then All will yield the results given in the top portion of Table 9.12. Note also that if one were interested in performing the ANOVA that is given in the middle portion of Table 9.12, all that would be required is to remove block from the model line and the from /DESIGN line (as well as to remove the block by task interaction (block*task) from the /DESIGN line). To replicate the ANCOVA results given in the lower portion of Table 9.12, all that would have to be done is to remove block from the model line and the from /DESIGN line (as well as to remove the block by task interaction (block*task) from the /DESIGN line), and include a WITH statement on the model line for x (y BY task WITH x) and add x to the /DESIGN line.