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was given. As it was stated in the previous section, the test was a writing test. The students were asked to make an advertisement text. The post test was conducted
on August, 9
th
2010. 4
Scored the result of the test 5
Determined the means of the result of the two groups 6
Compared the two means by applying t-test formula 7
Consulted the t- test value with the critical t- value at the 5 0.5 alpha level of significance.
3.2 Subject of the Study 3.2.1
Population
Margono 2003:118 defines population as a complete set of individuals or subjects having common observable characteristics. Best 1981: 8 states a
population is any group of individuals that have one or more characteristics in common that are of interest to the researcher. The population may be all the
individuals of a particular type or a more restricted part of that group. Population is very essential means of data collection in research. In this study, I chose the
third year students of SMPN 1 Adiwerna, Tegal in the academic year of 20102011 as the population. The total number of population was 351 students
divided into 9 classes.
3.2.2 Sample
According to Best 1981:8 a sample is a small proportion of the population selected for observation and analysis.
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Arikunto 1998: 107 gives an indication to take the sample. If the population is less than 100, it is better that all of the population is used as samples,
but if the population is more than 100, the researcher can take 10-15 or 20- 25 as sample. Since the population in this study was large enough, I took some
members of the population as sample; here I took 20 of the population that was 70 students.
There are many sampling techniques used in the investigation. According to Saleh 2001: 34-36 there are four sampling techniques namely:simple random
sampling, stratified random sampling, cluster random sampling, and systematic random sampling.
In order to select the students who would participate as the sample of this study, a simple random sampling techniques was applied. On the basis of these
data, I took IXF and IXG as the samples. They were taken randomly as experimental class and control class. In this study, I chose 70 students 35
students in each two class.
3.3.3 Variables of Investigation
Best 1981:59 states variables are the conditions or characteristic that the experimenter manipulates, control, or observes. Saleh 2001: 25-26 points out
there are five kinds of variables: dependent variable, independent variable, moderator variable, control variable, and intervening variable.
Dependent variable is factor which is measured or observed to determine the effect of independent variable. While independent variable is factor which is
measured, manipulated, or selected by the experimenter to determine its
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relationship to an observed phenomenon. Moderator variable is factor which is measured, manipulated, or selected by the experimenter to discover whether it
modifies the relationship of independent variable to an observed phenomenon. Control variable is factor which is controlled by the experimenter to neutralize an
effect they might have on the observed phenomenon. And intervening variable is factor which theoretically affects the observed phenomenon but can not be seen,
measured or manipulated. The variables in this study are:
1 The independent variable is the use of newspapers as media in teaching
advertisement text. 2
The dependent variable is the students’ achievement in the test score.
3.3 Instrument of Collecting Data
