post-test data between the experimental and the control groups was normally distributed.
4.1.3.2 Post-test Homogeneity The test of homogeneity of variances was performed to get the result of the post-
test homogeneity. The output of the test is showed in table 4.7 below:
Table 4.7 Test of Post-test Homogeneity of Variances
Score Levene Statistic
df1 df2
Sig. 2.962
1 30
.096
The data was homogeneous, if the significant value was higher than the
significant 5. From the table above, the significant value was 0.096. Because the result was higher than significant 5, the post-test data between the experimental
and the control groups washomogeneous.
4.1.4 Testing Hypothesis I
In the hypothesis I, the writer stated that there was a significant difference in the students‟ achievement of academic vocabulary mastery between the experimental
and the control groups. In order to analyse the significant difference between the experimental and the control groups, t-test statistical analysis was applied and it
used post-test scores of the two groups. By applying the t-test analysis, the writer could accept or reject the null hypothesis. The results of the t-test statistical
analysis are provided in table 4.8 below:
Table 4.8 T-test Statistical Analysis
Group Statistics
Group N
Mean Std. Deviation
Std. Error Mean Score
Experimental Group 16
73.62 5.898
1.474 Control Group
16 65.44
8.733 2.183
Independent Samples Test
Levenes Test for
Equality of Variances
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
Score Equal variances
assumed 2.962 .096 3.108
30 .004 8.188
2.634 2.807 13.568
Equal variances
not assumed
3.108 26.327 .004 8.188
2.634 2.776 13.599
The analysisof the homogeneity revealed that the two groups had the same variances or homogeneous, so the information from Equal variances assumed was
used to interpret thet-test result. Based on the table 4.8, the significant value of the t 2-tailedwas 0.004.Because it was lower than the significant 5, it was
concluded that there was a significant difference inthe students‟ achievement
between the experimental and the control groups in mastering academic vocabulary.
4.1.5 Testing Hypothesis II
The hypothesis II was tested by using normalized learning gain formula based on Meltzer 2002: 1260 to find out how effective List-Group-Label LGL strategy
contributed to the students‟ academic vocabulary mastery. The value of g is
presented in table 4.9.
Table 4.9 Post-test and Pre-test Mean Scores of Experimental Group
Experimental Group Post-test
73,625 Pre-test
54,187 The value of g
0,42429
It was determined that the value of the normalized gain gof the experimental group was 0.42. Therefore, it could be defined that
the percentage of the students‟ improvement in mastering academic vocabulary was 42.
4.2 Discussion
