confused word. For example; the writing is irrelevant with the topic, and one score means that so many mistakes.
Most of the students get the score between 1 until 3. For example, in vocabulary aspect, one student get three scores means that the words have
already been related to the topic and situation; however, they are not have any variation yet. Four students get two scores which mean that there are still lots
of unappropriate word used in the students write. From the table it can be seen that although the score is not high enough, the students can write and
understand what the instruction gives.
2. Pretest Result
Pre-test was conducted on August 13
st
, 2014 to 25 students in class XI A and 25 students in class XI B 20142015. Students’ writing in pre-test
was evaluated based on the rubric of Brown which covers content, vocabulary, generic structure, and language features. Later, the scores were
statistically analyzed by using SPSS 20.0 for windows by following several steps.
Normal Distribution Test
The normality test was employed by using Kolmogorov-Smirnov test to know whether or not the score of the students were normally distributed.
Before examining the normality of the scores, the hypotheses null and an alternative hypothesis were established. The result of the analysis is
presented in the following table.
Table 4.2 Tests of Normality
Kolmogorov-Smirnov Shapiro-Wilk
Statistic df
Sig. Statistic
df Sig.
EXPERIMENTAL GROUP CONTROL GROUP
.148 .119
25 25
.162 .200
.949 .949
25 25
.239 .234
In the test, the level of significance was set up at 0.05. based on table 4.2, it shows that the asymp. Sig of pre-test data in XI A as the Experimental
Group and XI B as the Control Group are 0.162 and 0.200. it means 0.1620.05 and 0.2000.005. the result suggests that the null hypothesis is
not rejected but alternative hypothesis is rejected. Therefore, it can be drawn as a conclusion that the data of both groups are normally distributed.
Homogeneity of Variance
The homogeneity of variance test was accomplished after conducted normal distribution test. Levene test on SPSS 20.0 for windows was
employed to analyze the data and to find out the homogeneity of variance of experimental and control groups. The hypotheses proposed was null
hypothesis that stated the data variances were homogenous; and alternative hypothesis that stated the data variances were not homogenous. The
following table is the description of the test result.
Table 4.3 Test of Homogeneity of Variance
Levene Statistic df1
df2 Sig.
PRETEST Based on Mean Based on Median
Based on Median And with adjusted df
Based on trimmed mean .016
.011 .011
.017 1
1 1
1 48
48 47.701
48 .900
.918
In the table 4.3, the asymp.sig is higher than the determined level of signficance 0.05, which also can be stated that 0.9000.05. It indicates that
the null hypothesis is not rejected but the alternative hypothesis is rejected. It draws a conclusion that the variance of data is homogenous. It also implies
that the analysis of t-test can be conducted since the data is normally distributed and the variances are homogenous.
Independent t-test
Lastly, independent t-test was calculated to see the equity of the data between XI A and XI B student’s score means. T-test determines if there is a
significant difference between the means of two data sets. The hypotheses established in this analysis were null hypothesis and alternative hypothesis.
Null hypothesis proposed t hat the students’ scores are not significantly
different; and alternative hypothesis proposed that there is a significant difference of means between the two groups. The table below is the result of
independent t-test conducted on pre-test scores.
Table 4.4 Independent Samples Test
Levene’s Test For
Quality of Variance
t-test for Equality of Means
F Sig.
T Df
Sig. 2- tailed
Mean Difference
Std. Error Difference
95 Confidence Interval of the
Difference Lower
Upper Pretest Equal variance
assumed Equal variance not assumed
.016 .900
-.058 -.058
48 47.930
.954 .954
-.04000 -.04000
.68896 .68896
1.42525 1.42530
1.34525 1.34530
The level pf significance established in this test was 0.05 with df = 48. Based on the statistical analysis illustrated on the table 4.4, it can be
explained that the significance value is higher than 0.05 or 0.9540.05. the result ensures that the null hypothesis is not rejected but the alternative
hypothesis is rejected. Therefore, there is no difference between control and experimental groups’ means.
By the result of the normality, homogeneity, and independent t-test above, it is apparent that both of the groups have equal initial ability in
writing argumentative text. Therefore, class XI A and XI B can be grouped as
