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CHAPTER 3. RESEARCH METHOD
This chapter discusses the research methods that were applied in the research. It covered research design, area determination method, respondent
determination method, operational definitions of the term and data analysis method.
3.1 Research Design
A researcher needs a research design before conducting the research. Research design is a strategy to arrange the setting of a research to get valid data
that match with the variable and the objective of the research Arikunto, 2006:44. The aim of this research was to investigate whether or not there was a significant
effect of using single picture on the eighth grades students’ descriptive text writing achievement at SMP Negeri Rogojampi Satu Atap in the 20142015
academic year. The research design that was used in this research was a quasi experimental
design with non-equivalent group post test only design .
This design can be used when the true experiments cannot be done. This problem appeared because the
educational administrator did not allow the random selection of students out of classes for experimental sample. Without randomization, there are no true
experiments. According to Yount 2006, the term quasi means almost, near, partial, or somewhat. So, this design has been developed for these situations that
are “almost true experiments” or quasi-experimental design. Nonequivalent-group posttest only design consisted of administering an
outcome measurement to two group or to a program or a treatment group and comparison. As Marczyk et al 205:138 say that in the nonequivalent groups
posttest-only design, one group the experimental group receives the intervention while the other group the control group does not. In addition, this design
controls for a simple testing effect and the interaction between testing and treatment by giving no pretest to either group. Jackson 2011:149 states that the
control group is nonequivalent, so there is no assurance that the two groups are at all equivalent on any variable prior to the study.
In this design, two classes were chosen as the experimental and control groups from the four available classes of the eighth grade of SMPN 4 Rogojampi
Satu Atap. Two similar classes were chosen by using homogeneity analysis and lottery was used to determine the control group and the experimental group. The
experimental group was taught descriptive text by using single pictures while the control group was taught writing a descriptive text without using single pictures.
Then, after the treatment, the writing posttest was given to both the experimental and the control groups to know the difference of the writing achievement between
them. The research design can be illustrated as follows:
Group Treatment
Posttest A
X O
B O
Note: A: Experimental group
B: Control group X: Treatment for experimental group
O: Posttest Beier,
2010:2 The steps of the research design were as follows.
1. Conducting the homogeneity analysis on the students’ English previous semester score of all classes of the eighth grades at SMP Negeri 4
Rogojampi Satu Atap in the 20142015 academic year. 2. Analyzing the scores of students’ previous semester score by using
ANOVA formula. When the analysis is more than 0.05, it means that there
is no significant difference in their score so that the researcher can select any two classes as the sample. If the analysis result is less than 0.05, it
means that the samples are heterogeneous that the researcher should select two classes which have the nearest means based on the students’ English
previous semester scores. 3. Determining the experimental group and the control group by lottery, since
the population was homogenous. 4. Giving the treatment to the experimental group by teaching writing a
descriptive text by using the single pictures as media while the control group was taught descriptive text writing without using the single pictures
as media. 5. Giving the writing test to both the experimental and the control groups to
measure the students’ writing achievement of descriptive text after the treatment.
6. Analyzing the results of the writing post test by using SPSS to know whether the mean difference is significant or not.
7. Drawing a conclusion based on the results of the data analysis to answer the research problem.
3. 2 Area Determination Method
The research area in this research was decided by using purposive method. It is determined purposively based on certain reasons McMillan, 1992:76. The
researcher chose SMPN 4 Rogojampi Satu atap as the research area based on some reasons. First, the eighth grade students at SMP Negeri Rogojampi Satu atap
is never taught writing by using single pictures. Second, there was no previous research finding that was done by using single pictures in teaching writing in that
school. Third, the researcher got permission from the headmaster to conduct the experimental research.
3.3 Respondent Determination Method
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