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short, considering the explanation above, this experimental study used two groups, namely experimental group and control group.
The third variable is a secondary independent variable. It is selected to determine if it affects the relationship between the primary
independent variable
teaching materials:
computer based
communication and textbook and motivation. In this study, learning motivation as the last variable that was labeled with two different
names, i.e high learning motivation and low learning motivation.
C. Research Design
In this study, the writer used a factorial design to extend the number of relationships that examined. Fraenkel and Wallen 1993:
255 propose that they are essentially modification of either the post test only control group or pre test-post test control group designs,
which permit the investigation of additional independent variables. As an experimental study, there are at least two groups in this
experiment, namely control group and experimental group. The control group is the class that is taught by using textbook and the experimental
group is the class that is taught using computer based communication. They were given different treatments. After the treatment, the groups
were given a post test. In addition, before the treatment, the writer also gave a questionaire about learning motivation. The students‟ learning
motivation is classified into high and low. By so doing, the writer
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found out what teaching materials used to teach high motivated students and low mativated students.
The proposed experimental design of the independent and dependent variables can be seen at 2 by 2 Factorial Design as follows:
Table 3.2
Main Effects
Simple effect
A
1
Commputer Based
Communication A
2
Textbook High learning
motivation B
1
A
1
B
1
A
2
B
1
B
1
Low learning motivation
B
1
A
1
B
2
A
2
B
2
B
2
A
1
A
2
Note: A
1
: The mean score of writing test of experimental class which is taught using Computer Based communication.
A
2
: The mean score of writing test of control class which is taught using textbook.
B
1
: The mean score of writing test of students having high learning motivation.
B
2 :
The mean score of writing test of students having low learning motivation.
A
1
B
1
: The mean score of writing test of students having high learning motivation who are taught using Computer Based
Communication.
