Exhibit 11.3: The following graphs show the results of two studies comparing the effect of instructional Methods A and B in large and small social studies classes.The dependent variable was scores on a standardized social studies test.

-Refer to Exhibit 11-3.Which graph shows main effects but no interaction?
A) graph (a)
B) graph (b)

Question

Exhibit 11.3: The following graphs show the results of two studies comparing the effect of instructional Methods A and B in large and small social studies classes.The dependent variable was scores on a standardized social studies test.
 
-Refer to Exhibit 11-3.Which graph shows main effects but no interaction?
A) graph (a) 
B) graph (b)

Quizplus · Accepted Answer

Graph (a) shows a clear main effect of instructional method, where Method B consistently resulted in higher test scores than Method A. There is no apparent interaction between instructional method and class size, as the results are consistent across both large and small classes. Graph (b) shows a possible interaction, as the effect of instructional method seems to differ based on class size.