improvement of students in their vocabulary achievement after the treatment.
E. Technique of Data Analysis
The technique of data analysis will use the t-test formula that is adapted from Suharsimi Arikunto.
1
The t-test is used to compare the score in pre-test and posttest. After getting the score from pre-test and post-test, the writer
analyzes it by using statistic calculation of T-Test formula with the degree of significance 5.
The t-test formula can be formulated as follow:
t
=
= Mean of the Gained Score of Experiment Class = Mean of the Gained Score of Controlled Class
= Standard Deviation of Experiment Class = Standard Deviation of Controlled Class
= Number of students in Experiment Class = Number of students in Controlled Class
In order to get the calculation of T-test, there are several steps to be taken:
The following steps describe as follows:
1. Determining mean of gained score of experiment class:
=
1
Suharsimi Arikunto, Prosedur Penelitian Suatu Pendekatan Praktik, Sixth edition, Jakarta: Asdi Mahasatya, 2006, p. 311
Mean of score in Experiment Class
= Gained score of Experiment Class
=
Number of students in Experiment Class
2. Determining standard deviation of Experiment Class
= Standard deviation = Squared of gained score in Experiment Class
= Gained score of Experiment Class = Number of students in Experiment Class
3. Determining mean of gained score in Controlled Class
=
= Mean of score in Controlled Class
= Gained score of Controlled Class
=
Number of students in Controlled Class
4. Determining standard deviation of Controlled Class
= Standard deviation = Squared of gained score in Controlled Class
= Gained score of Controlled Class = Number of students in Controlled Class
5. Determining value of hypotheses testing
t
0 =
= Mean of the Gained Score of Experiment Class = Mean of the Gained Score of Controlled Class
= Standard Deviation of Experiment Class = Standard Deviation of Controlled Class
= Number of students in Experiment Class = Number of students in Controlled Class
6. Determining Degree of Freedom
df = degrees of freedom
= number of students of experiment class = number of students of control class
F. Statistical Hypotheses
Statistically, the hypotheses are expressed as follow: H
o
: μ
A
μ
B
H
a
: μ
A
μ
B
In which: H
o
: Null Hypothesis H
a
: Alternative Hypothesis
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