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difference of the samples. Thus, the Levene’s test is employed. The sample is said to be homogeneous if the value of F-observed F
o
is lower than F-table F
t
or if the probability significant level is higher than 0.05.
Using the SPSS 16.0 for windows, the results of the homogeneity test of the pre-test is presented in Table 21. Meanwhile, the result of homogeneity test of
the post-test is shown in Table 22.
Table 21: Result of the Homogeneity Test of the Pre-test Data
df
1
df
2
F
o
F
t
P
value
α Interpretation
Pre-test 1
52 2.829
4.02 0.099
0.05 homogeneous
Table 21 shows that the score of F
o
is lower than F
t
with the significance level 0.05. Moreover, p
value
of the pre-test is higher than the significance level 0.05. Therefore, it can be interpreted that the relationship is homogeneous.
Table 22: Result of the Homogeneity Test of the Post-test Data
df
1
df
2
F
o
F
t
P
value
α Interpretation
Post-test 1
52 0.236
4.02 0.629
0.05 homogeneous
Table 22 shows that the score of F
o
is lower than F
t
with significance level 0.05. In addition, p
value
of the post-test is higher than significance level 0.05. Therefore, it can be said that the relationship is homogeneous.
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2. Hypothesis Testing
After describing the normality and homogeneity of the tests, the researcher conducts the hypothesis testing to determine whether the hypothesis is acceptable
or not. The hypothesis in this study says There is a significant difference in simple present and simple past tenses mastery between the grade tenth of senior
high school students who are taught using Authentic Materials and those who are not. In this analysis, the t-test formula is applied to measure the level of the
difference and significance. However, the hypothesis must be changed to the null hypothesis Ho before the hypothesis is rejected or accepted. The null hypothesis
Ho states that There is no significant difference in the simple present and simple past tenses mastery between the tenth grade senior high school students
who are taught using Authentic Materials and those who are not. The hypothesis is tested by finding the mean difference between the post-
test mean scores of the experimental and that of the control groups. After the mean difference is found, the t-test formula is applied to know whether the
difference is significant or not. From the post-test, it is found that t-observed is 5.430 while t-table is 1.68. In the meantime, t-test shows that the p
value
is 0.000, the significance level is 5, and the degree of freedom is 52. Statistically, if t-
observed is higher than the value of t-table, the null hypothesis Ho is rejected and the alternative hypothesis Ha is accepted or there is a significant difference.
However, if t-observed is lower than the value of t-table, the null hypothesis Ho is accepted and the alternative hypothesis Ha is rejected or there is no significant
difference.
