was conducted. The calculation was performed manually by using the following formula developed by Coolidge.
1
The t refers to the t value obtained from the independent t-test calculation on post-test data. Afterward,
the df is the amount of samples minus by 2 df = N-2 √
Derived from table 4.7, t value is 2.753 and df is 48. Hence, after completing the computation, it is found that r value is 0.369. converted to the
effect size table see table 3.1, the obtained value shows medium effect size.
4. The Paired t-test Analysis on Experimental Group Scores
A paired t-test was conducted to discover the differences in experimental group score before and after the students were given the
treatments. The calculation of paired t-test was used to analyze the score of the experimental and control groups.
Table 4.8 Paired Samples Statistics Pre-Test and Post-Test Experimental
Group
Mean N
Std. Deviation Std. Error Mean
Pair 1 PRETEST POSTEST
12.0400 13.6400
25 25
2.38886 1.95533
.47777 .39107
1
Frederick L. Coolidge, Statistic A Gentle Introduction. London: Sage Publications Ltd., 2000 p. 105
Table 4.9 Paired Samples Test
Paired Differences
t df
Sig. 2-tailed Mean
Std. Deviation
Std. Error
Mean Lower
Upper Pair
1 PRETEST-
POSTEST -1.60000
1.65831 .33166
-2.28452 -.91548
-4.824 24 .000
Based on the result, the experimental group students’ scores on post- test were better in which the mean=13.64 than their scores on pre-test the
mean=12.04. in addition, the two-tailed value of p was 0.000 which was lower than 0.05. In conclusion, the calculation of paired t-test showed that
there was a significant difference between the pre-test and post-test scores of experimental group. Thus, the null hypothesis was rejected because there was
a significant difference between pre-test and post-test in experimental group. It can be concluded that the use of style writer computer software as
treatment in teaching argumentative text to improve studen ts’ ability in
revising their writing was effective. The calculation was carried out in order to know how well the
treatment worked, in term of pre-test and post-test scores for experimental group. The t value of 4.824 and df of 24 were obtained from paired sample t-
test analysis. The result represented effect size with the value of r = 0.70 according
to Coolidge, the value of r was large effect. Thus, there was major effect of s
tyle writer in students’ability in revising the argumentative text, in other word, the treatment worked very well.
B. Discussion
The aims of this research were to investigate whether or not style writer computer software is effective
in improving students’ ability in revising their writing result.
The statistical computation on the pre-test scores of the experimental and control group using SPSS 20.0 for windows show that the distribution of the
experimental and control group’s scores are normally distributed. Since the pre-test scores of the experimental and control groups are normally
distributed, it means a parametric test using t-test should be used. Brown states that there are two requirements to be able to make assumption from t-test
result, the score in each group were normally distributed and variance of the score of the two groups are equal. An independent sample test using t-test
shows that both of the control and experimental groups are homogenous. The improvement of students’ writing skill can be seen from the effect size
t value is 0.008 and df is 48. It is found that r value is 0.369. it means that there is a significant im
provement in students’ ability in revising the argumentative writing result. To support the data, paired sample test was
represented. It can be seen from average pre-test score 12.04 and the average of post-test 13.64. it is increased 1.6 point, which is means that style writer
has influence in revising argumentative writing.
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CHAPTER V CONCLUSIONS AND SUGGESTIONS
A. Conclusions
According to the findings and the conclusions of the research, a conclusion can be drawn as follows:
Style writer computer software, one of the alternative media in revising and editing argumentative text,
is effective to improve the students’ ability in revising argumentative writing result. The exprimental study shows that the
improvement in writing argumentative text of the experimental group is statistically significant than the improvement in control group 0.0080.05, r
= 0.369.
B. Suggestions
There are several suggestions proposed for the next studies in the similar field as the present research; first, in the treatment process, the students have
some difficulties in understanding the instruction. The teacher should pay attention more by giving clear instruction before students use style writer
computer software by their own selves. Second, the research uses pre-experimental design which employs limited
sample and weaker than another experimental design. For that reason, it is suggested for the next researcher on this technique to involve larger samples
and to strengthen the design to make the research better. Third, the style writer computer software used in this research effectively
improved students skill in revising their writing. It is important for the next researcher to know whether this software appropriate applied in other kind of
writing. Last is the research is conducted on eleventh grade of high school in Tangerang Selatan. Hence, further research should prove whether style writer
computer software is also effective for students in different grades.
