CT OM EEG TM MIU 9/14

The second hypothesis was that MIU freshmen would not perform significantly different from established norms for other liberal arts freshmen. This hypothesis was tested using the table of norms (Table 1c) in the Watson-Glaser Critical Thinking Appraisal Manual. The percentile ranks in this table were based on results from 5,297 freshmen at 15 liberal arts colleges in 13 states. According to this table, the mean score on the WGCTA of 70.53 would place the average MIU freshman score in the 45th percentile, slightly below average.

The freshmen WGCTA was also tested against the mean score for South Australian high school seniors (Lucas, 1972) by a t-test and no significant difference was found. These two methods of comparison led to the confirmation of the second hypothesis.

The third hypothesis was that MIU seniors would outperform established norms for liberal arts college seniors. This hypothesis was tested using the Table 1d in the WGCTA Manual. The percentile ranks for this table were obtained in a study with 554 first-semester senior women at ten liberal arts colleges for women in seven states (Haas, 1963). According to this table, the seniors' mean score of 83.17 would place the average MIU senior in the 83rd percentile. Seniors at MIU were thus higher in CT with respect to their peers, than MIU freshmen were.
 

Table 3

Correlations between the
subtests of the Watson-
Glaser Critical Thinking
Appraisal and Total score

Table 3a

Comparison of Subtest Intercorrelations and
Subtest-Total Correlations for the
Watson-Glaser Critical Thinking Appraisal cited
In Various Research Studies

Key

The mean WGCTA scores for seniors were also compared with mean scores provided in Table 2 in the WGCTA Manual.  This table showed scores from job applicants at a manufacturing company, and from employees who were college graduates. The MIU seniors significantly outperformed the job applicants (t=3.31, df=60), and outperformed the
college graduates, although not significantly (t=1.6, df=63).  Due to the
high percentile ranking according to table 1d, 33 percentile points above average, the third hypothesis was accepted, but further norms for comparison should be sought.

The fourth hypothesis stated that the subtests of the Watson-Glaser Critical Thinking Appraisal would correlate significantly with the total score as shown by Table 3, all subtests correlated positively with the total score, and with each other. Thirteen out of the fifteen possible combinations were statistically significant positive correlations. The correlations between Evaluation of Arguments and Inference, and between Deduction and Recognition of invalid Assumptions were not
significant.

The correlation between the total WGCTA score and Interpretation of arguments was the highest value·(r=.85) which was also the highest correlation in the correlational matrix for norms provided in the WGCTA Manual (Watson-Glaser, 1964, p.15). Thus the fourth hypothesis was not completely accepted, due to the positive, but not significant values.

Table 1

Watson-Glaser Critical Thinking
Appraisal means and standard
deviations of different groups

Table 2

Rokeach Adult Dogmatism Scale
means and standard deviations
of different groups