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CHAPTER III METHODS OF INVESTIGATION
This chapter presents methods of investigation. It includes population, sample, variables, experiment design which contains experimental research,
experiment, and procedure of experiment, instrument of the study, administration of the experiment, procedure of collecting data and method of analyzing data.
3.1 Population
Population is all the subjects of the study that would be investigated. Arikunto 2006: 130 quotes a definition of population from Encyclopedia of
Educational Evaluation. Based on Encyclopedia of Educational Evaluation, “a population is a set or collection of all elements processing one or more attributes
of interest.” Furthermore, Widi 2010: 197 states that “population is every group which is being the subject of the research.”
The population in this study was the eleventh grade students of SMA Negeri 2 Mranggen in the academic year 20102011. The total population was 279
students. It consisted of seven classes, four classes of science program IA and three classes of social program IS as listed below:
- XI IPA 1 = 38 students
- XI IPS 1 = 40 students -
XI IPA 2 = 38 students - XI IPS 2 = 42 students
- XI IPA 3 = 40 students
- XI IPS 3 = 41 students -
XI IPA 4 = 40 students
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I, then, chose two classes of science program, one class as the control group and the other one as the experimental group. Choosing the population was based
on the following consideration: 1
The eleventh grade students of SMA Negeri 2 Mranggen were not bothered by the preparation of having the national examination.
2 The eleventh grade students of SMA Negeri 2 Mranggen had obtained more
materials in learning English than those of the tenth grade students.
3.2 Sample
“A sample is a part or the representative of population that is investigated” Arikunto 2006: 134. Sugiyono 2009: 118 states that “a sample is a part of
population which has the same characteristics with the population”. Sample is part of selected number of people or things representing the whole population. The
representative of a sample determines the validity of the generalization of the result.
The population of this research was the eleventh grade students of SMA Negeri 2 Mranggen. Therefore, I decided to take two classes as sample. I took XI
IPA 2 as the experimental group and XI IPA 3 as the control group. Choosing the sample was based on the following consideration:
1 After I checked the average scores of the population on English subject, XI
IPA 2 and XI IPA 3 were in the same level or quality in English achievement. There was no significant difference between their scores.
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2 In addition, after I consulted her sample to the English teacher, he approved it
and also recommended those classes to make them as the samples of the experiment.
XI IPA 2 as the experimental group consisted of 38 students, but at the days when the pretest and the posttest were given to the students, a student was not able
to join because she was sick. As a result, there were 37 students in the experimental group. Then, for the control group, I chose XI IPA 3 which
consisted of 40 students. Unfortunately, at the days when the pretest and the posttest were given to the students, there were three students who were not able to
join. Two students were sick and a student was absent. As a result, the total student of the control group was same with the experimental group. There were 37
students for each group. The list of students’ names of XI IPA 2 and XI IPA 3 are on Appendix 9 and 10.
The students of the experimental group were taught writing narrative texts by using video clips containing music, song, and story, whereas the students of the
control group were taught writing narrative texts by using series of pictures as media. Video clips from Avril Lavigne entitled Alice Underground and Emily
Osment entitled Once Upon a Dream were used as media for teaching writing narrative for the experimental group. Meanwhile, the students of the control group
were taught by using series of pictures about Alice in the Wonderland and Sleeping Beauty.
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3.3 Variables
Kategori