c. Fill variable on Dependent List and fill another variable on Factor
box
d. Click Option and choose Descriptive and Homogeneity of
variance test
e. Click Continue until it comes back to One-Way ANOVA dialogue
box
f. Click OK
3 Making decision about significance levelprobability value p using significance degree 5 α = 0.05, the creteria in taking the decision
is; If the p robability value p ≥ α = 0.05, H
is accepted. Conversely, H
is rejected if the probability value p α = 0.05.
2. Hypothesis Test
This is the last step to analyze the data after the normality and the homogeneity test was done. Because the result of the experimental and the
control class’ pre and posttest’s score met the requirement of normality test and both the classes sample had similarity or homogeneity in variance, the
independent sample t test was able to be done to test the research hypothesis. The independent sample t test was used to compare the means or averages of
the two independent sample the experimental and the control class in order to determine whether there was statistical evidence which proved that the
means were significantly different. However, before testing the hypothesis, it had to calculate the independent sample t test of the experimental and the
control class’ pretest score first to see if there was no extreme difference in both the experimental and the control class’ pretest before the treatment was
given. To calculate the independent sample t test of both the experimental and the control class’ pretest, the following is the steps of doing the independent
sample t test: a. Making the hypothesis testing:
H : There was no extreme difference in narrative writing skill between the
experimental and the control class before the treatment was given. H
1
: There was extreme difference in narrative writing skill between the experimental and the control class before the treatment was given.
b. Calculating t value by using the Independent Sample t-Test on IBM SPSS Statistics 19. The steps are as follow:
17
1 Open file independent sample t test on CD, parametric statistic folder
2 Click Analyze = Compare Means = Independent-Sample T Test
on the menu until the dialogue box Independent-Sample T Test appears
3 Fill variable on the box Test Variables and fill another variable on the box Grouping Variable
4 Click Define Groups, fill dependent variable value on the box Group 1 and 2
5 Click Continue until it comes back to the dialogue box Independent-
Sample T Test 6 Click Options until the dialogue box Independent-Sample T Test:
Option appears. Determining Confidence Interval and Missing Values
7 Click Continue 8 Click OK
c. Making decision about t value on the row Equal Variance Assumed it is assumed that the variance is homogenous and using the degree of
significant 5 α = 0.05. The criteria of taking decision were: If t
count
t
table
or Sig 2-tailed
⁄
, H was accepted. Meanwhile, H
was rejected if t
count
t
table
or 2-tailed
⁄
α.
17
Ibid, pp. 112-113