Figure 3. Subjects' partial-report
performance as a function of recall
instruction, display-instruction
compatibility, and ISI in Experiment 1.
The ISI factor was significant [F(3,30) = 29.00, p < .05], as was the ISI x instruction
group interaction [F(3,30) = 3.68, p < .05]. None of the other factors or interactions was
significant.
To ascertain whether the basic large-capacity finding was obtained, the subjects'
partial-report performance at the various levels of ISI was compared with their
whole-report performance. For these comparisons, the subjects' whole-report
performance was treated as the control ISI level. Data were subjected to an overall 2
(instruction group) x 3 (display-instruction compatibility) x 5 (four ISI levels and whole
report) factorial ANOVA with repeated measures on the latter two factors. (For this
analysis, only the ISI factor and all interactions involving ISI are relevant.)
The ISI factor was significant [F(4,40) = 45.67, p < .05]. Also significant was the ISI x
instruction group interaction [F(4,40) = 2.71, p < .05]. None of the other interactions
involving ISI was significant. Subsequently, the Newman-Keuls multiple comparison test
was used to compare each of the four ISI levels with the whole-report condition
separately for the two groups of subjects. As can be seen from Table 2, partial-report
performance was superior to whole-report performance only at the 0- and 150-msec ISIs.
This is true for both the "row recall" and the "column recall" groups.
As can be seen from Table 1, every subject was tested twice under the practice,
compatible, incompatible, and irrelevant display-instruction conditions. The subjects'
partial-report performance at the 0-msec ISI in the two practice and the two test sessions
for each of the three compatibility conditions is shown in Figure 4. The obvious feature
of Figure 4 is that the large-capacity finding is obtained only after the subjects have 96
practice trials on the partial-report task.
To validate this interpretation, data from the subjects' partial-report performance and their
whole-report performance were subjected to a 2 (instruction group) x 3 (compatibility) x