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5. Because of the two month time period, maturation was
not expected to be a source of invalidity.
6. Because the selection was not based on scores, regression was not considered a source of invalidity.
For a more detailed discussion of invalidity sources related to this design, refer to Campbell and Stanley (18:56).
Hypotheses and Subhypotheses
In this study two major hypotheses were tested:
H1: There is no significant difference between the class
means on the pre- and posttest of the Pupil Questionnaire.
H2: There is no significant difference between the total
even scores of the experimental groups and control
groups on the observation instrument.
H2: 02<01 05<04 02<03 02<04
05<01
Ten subhypotheses under Hypothesis 2 were tested in this study:
hl: There are no significant differences in the individual comparisons between the experimental and control
groups for the variable, nature of the situation.
hl: 02<01 05<04 02<04 05<01
h2: There is no significant difference in the pre- and
posttest comparison for the variable, nature of the
situation.
h2: 02<03