the dependent variable. In this study, the independent variable is the use of subtitled English songs, while the dependent variable is the vocabulary mastery of
students.
2.3 Theoretical Framework
In conducting the present study entitled The Effectiveness of Subtitled English Songs to Improve the Vocabulary Mastery of Junior High School Students, the
writer concerns to students` vocabulary achievement. In her study, she uses a quasi-experimental design. She divides the subject of the study into two groups,
experimental group and control group. In experimental group, she teaches students by subtitled English songs, while in control group, she teaches the
students by Grammar Translation Method. When conducting the study, the writer designs vocabulary test as a main
instrument to collect the data between both groups and to compare the effectiveness of subtitled English songs and Grammar Translation Method in
improving students` vocabulary mastery. Before the writer gives a treatment, the pre-test is given for both groups to
measure students’ basic ability on vocabulary achievement. After giving the treatment, she gives post-test in both groups to measure the significant differences
of students` vocabulary achievement between experimental group and control group.
After finding the result of the test, the writer calculates the computation of the mean score using the t-test formula. The mean scores are compared in order to
know whether there is a significant difference between pre-test and post-test between the two groups or not and to know which is more effective to teach
vocabulary. The theoretical framework of the present study visualized below:
Figure 2.1 Theoretical Framework
Control group PRE-TEST
Experimental group TREATMENT
Using Grammar Translation Method
POST TEST Using subtitled
English songs
Experimental group’s post-test
mean score
Control group’s post- test mean score
Comparing the scores using t-test formula
Define which one is more effective to improve students’ vocabulary mastery
20
CHAPTER III RESEARCH METHODOLOGIES
Here, several sub-chapters are going to be discussed. There will be research design, subjects of the study, population of the study, sample and sampling
technique, variables of the study, type of data, instrument of the study, method for
collecting the data, result of try out test, and the last is statistical design.
3.1 Research Design
In order to conduct this study, the writer used quasi-experimental research design in the form of nonequivalent control group design. As mentioned by Nunan
1992:41, in an experimental study, there are quasi-experimental design, pre- experimental design, and true-experimental design.
In this study involved two groups: an experimental group and a control group. The first group was given the treatment using subtitled English songs and
the last group was taught with Grammar Translation Method. A pre-test was given to both groups before the treatment and a post-test was given after the treatment.
The result of the tests in both groups was analyzed using t-test formula to see the influence of the treatment.
Nunan 1992:26 stated: Much research in education today conforms to a design in which a
single group is studied only once, subsequent to some agent or treatment presumed to cause change. Such studies might be
diagramed as follow:
