XO [X = the treatment administered to the subjects, and O = the
observations.] Convinced by this argument, your next inclination is to test groups,
one which has used the innovative materials and one which has not.
Table 3.1 The Research Design
The experimental group E
1
, received a treatment X
1
of using subtitled English songs while second group, the control group C
1
received a treatment X
2
of using Grammar Translation Method. Here, the two groups received pre- test O
1
and O
2
to obtain first data. In addition, the experimental group E
1
was given treatment X
1
of using subtitled English songs while the control group C
1
was given treatment X
2
of using Grammar Translation Method. Finally, both the experiment group E
1
and the control group C
1
were given post-test O
3
and O
4
to obtain second data. The effectiveness of subtitled English songs and the relative improvement of the two groups could be seen from the gain score that
was the post-test minus the pre-test score of the two groups.
3.2 Subjects of the Study
The subjects of this study was the students’ enhancement on vocabulary by using
subtitled English songs especially for the eighth grade students of SMPN 39 Semarang in the academic year 20142015.
Group Pre-Test
Treatment Post-Test
Experimental E
1
O
1
X
1
O
3
Control C
1
O
2
X
2
O
4
3.3 Population
In order to get the result of this study, the writer had to determine the population first. The researcher chose the eighth grade students of SMPN 39 Semarang in
academic year 20142015 as the population of the research. The number of the students is 285, which are divided into nine classes.
SMPN 39 Semarang is located at Sompok Street 43 A, Semarang. The researcher chose SMPN 39 Semarang as the population because it was a school
when the researcher did her PPL in seventh semester, she found problems especially when the students learned vocabulary, so the researcher chose the
population to conduct this study in enhancing students ’ vocabulary mastery.
3.4 Sample and Sampling Technique
The writer used quasi-experimental research in her study. The problem was in randomly selecting and assigning individuals to the experimental and control
group. Thus, the writer chose to use available classes as the samples by using nonprobability sampling as the sampling technique.
In this study, the writer selected two classes as the samples by assigning them into two groups; one group was as the experimental group and another was
as the control group. The experimental group received the treatment used subtitled English songs, and the control group used Grammar Translation Method. Class
VIII-G and class VIII-H are chosen to be the sample because both of these class have the same number of students. These classes also have the same environment
around the classroom. In addition, the students from the two classes have almost the same mean score in the first semester test.
3.5 Variables
