Validity Test Data Collection Technique
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7. Determining standard error of different mean of variable x and mean of variable Y:
�
−
= √� + �
M
x
= mean of students post-test score in experiment class
M
y
= mean of students’ post-test score in control class
∑ fx
= sum of students’ post-test score of experiment class
∑ fy
= sum of students’ post-test score of control class
N
x
= number of students’ in experiment class
N
y
= number of students in control class
SD
x
= standard deviation of mean in experiment class
SD
y
= standard deviation of mean in control class
SE
Mx
= standard error of mean in experiment class
SE
My
= standard error of mean in control class
SE
Mx-My
= standard error difference between Mx and My
t
= value of hypothesis testing After all of the data calculated, determine the degree of freedom with formula:
df = N
x
+ N
y
– 2
8. Normality Test Normality test used to know whether the data collected are normal on the
distribution or not. The researcher will use IBM SPSS Program version 23 to find out the normality of the data.
Steps: a Open IBM SPSS 23 program, to find out the normality data, the researcher
used Descriptive Statistic formula
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b First, write the variable view with Score for pretest or posttest score and Class for experimental or control class
c Then, click Analyze→Descriptive Statistics→Explore
d Drag the Score to the Dependent List and Class to the Factor List e
Click Plot→checklist Normality Plots with Test→OK
The criteria of determining the normality of the data was: a If L
value
is smaller than L
table
L
value
L
table
, it means that the data were distributed normally.
b If L
value
is bigger than L
table
L
value
L
table
, it means that the data were not distributed normally.
2. Homogeneity Test Homogeneity test is used to determine whether the data is in homogeneity
variance or not. Below are the steps to calculate the homogeneity data: a Open IBM SPSS 23 program, for homogeneity test, the researcher used one-
way ANOVA formula. b First, write the variable view with Score for pretest or posttest score and Class
for experimental or control class c
Click Analyze→Compare Means → One-way ANOVA d Drag the Score to the Dependent List and Class to the Factor List
e Click Option→checklist Homogeneity of Variance Test→OK