a. The Data of the Pre-test Scores of the Experimental Class
Based on the result of statistical calculation by using SPSS 13.00 for windows computer program, the mean score was 57.89 with the standard
deviationof 8.73. The maximum score was 75 and the minimum score was 35. The statistical data can be seen in Table 9 while the complete data analysis is in
Appendix C.
Table 9: Descriptive Analysis of the Experimental Class in the Pre-test N
Mean Std.Deviation Minimum
Maximum Pre-test
32 57.89
8.73 35.00
75.00
Meanwhile, the frequency distribution of the pre-test score on the experimental group is presented in Table 10.
Table 10: Frequency Distribution of the Pre-test score on Students’ Writing Ability of the Experimental Class.
No Interval
f Percent
Cumulative Percent
Categorization
1. 87.5 – 99.9
Excellent 2.
75.0 – 87.4 1
3.1 3.1
Very Good 3.
62.5 – 74.9 10
31.3 34.3
Good 4.
50.0 – 62.4 17
53.1 87.5
Fair 5.
36.5 – 49.9 3
9.4 96.6
Poor 6.
25.0 – 37.4 1
3.1 100.0
Very Poor
Table 10 shows that there was no student classified into excellent. There was 1 student 3.1 in very poor category, 3 students 9.4 in poor category,
17 students 53.1 in fair category, and 10 students 31.3 in good category.There were 21 students 65.6 achieving scores below the ideal mean
62.5 in very poor to fair category. It can be concluded that most students 65 belong to poor category on the pre-test or before they were given treatment of
using inquiry based-learning strategy.While, the studentswho belong to good category was 34.
b. The Data of the Post-test Scores of the Experimental Class
Based on the result of statistical calculation by using SPSS 13.00 for windows computer program, the mean score was 82.10 with the standard
deviation 7.46. The maximum score for the post-test of the experimental group was 92.50 and the minimum score was 67.50. The statistical data can be seen in
Table 11.
Table 11: Descriptive Analysis of the Post-test of the Experimental Class N
Mean Std.Deviation
Minimum Maximum
Post-test 32
82.10 7.46
67.50 92.50
Meanwhile, the frequency distribution of the post-test score on the experimental group is presented in Table 12.
Table 12: Frequency Distribution of the Post-test score on Students’ Writing Ability of the Experimental Class
No Interval
f Percent
Cumulative Percent
Categorization
1. 87.5 – 99.9
12 37.5
37.5 Excellent
2. 75.0 – 87.4
15 46.9
84.4 Very Good
3. 62.5 – 74.9
5 15.6
100.0 Good
4. 50.0 – 62.4
100.0 Fair
5. 36.5 – 49.9
100.0 Poor
6. 25.0 – 37.4
100.0 Very Poor
Table 12 shows that there was no student classified into poor and very poor category. There were 5 students 15.6 in good category, 15 students
46.9 in very good category and 12 students 37.5 in excellent category on the post test or after they were given treatment using inquiry based-learning
strategy. It means that most students belong to good category after the treatment given.
c. Comparison Data between the Pre-Test and Post-Test of the
Experimental Class
The result of the pre-test and post-test scores of the experimental class is compared to find out the difference of students’ writing ability before the
treatment is conducted. The comparison between both scores are presented in Table 13.
Table 13: Statistical Data of the Pre-Test and Post-Test Scores of the Experimental Class
Data Pre-Test
Post-Test Number of cases
32 32
Mean
57.89 82.10
SD
8.73 7.46
Based on Table 13, the mean score of the pre-test of experimental class was 57.89 which were classified into fair category. Meanwhile, the mean of the
post-test was 82.10 which were classified into very good category. The data show that the mean score of the post-test was higher than that of pre-test score. It can be
seen from the improvement of the scoring categorization from fair to very good category. It means that the writing ability of the experimental class significantly
improved 24.21 points after treatment given, that is, by using inquiry based- learning strategy.
Further, the standard deviation SD for the pre-test was 8.73, while the post-test was 7.46. This shows that the SD of the post-test was lower than the SD
of the pre-test. If the SD of the post-test was lower than the SD of the pre-test, it
can be interpreted that students’ writing ability of the experimental class on the pre-test on post-test score became homogenous.
In addition, on the pre-test there were 34.4 of students in good category which achieved scores above the ideal mean and 65.6 of students in poor
category which achieved scores below the ideal mean. The pre-test score on the student’s writing ability of the experimental group did not achieve the ideal mean
because the score of most students was below the ideal mean. Besides, the percentage of students achieving scores below the ideal mean were higher than
those achieving score above the ideal mean i.e. 65.6 34.4. It meant that the result of the pre-test score on the students’ writing ability of the experimental
group was classified into the poor category. On the other side, on post-test, all of students were 100 in good
category and achieved scores above the ideal mean and there are no students in poor category who achieved scores below the ideal mean. The post-test score on
the students’ writing ability of the experimental group achieved the ideal mean because the score of all students were above the ideal mean. Briefly, there was
improvement 65.6 from the pre-test to post-test in experimental class.
2. Control Class
The data of control class are divided into three sections: the data of the pre-test score, the post-test score and the comparison between both of them. The
data of the pre-test score and post-test score of the control class are explained as follows.
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