
205Analyses of Single Samples
above the cutpoint. The observed proportion of students who scored at or
below the cut point is signicantly greater than the observed proportion of
students who scored above the cut point (0.40 and 0.60, respectively). We can
conclude that the predicted success rate (0.80) is signicantly different from
the observed rate (0.60) at the 0.05 level of signicance.
Now that the teacher knows that the predicted success rate of students
is different from the observed success rate, she can focus her attention on
the causes for the difference and make decisions about the next steps in the
instructional process.
As we can ...