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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.
64
A
2
B
1
: The mean score of writing test of students having high learning motivation who are taught using textbook
A
1
B
2
: The mean score of writing test of students having low Learning motivation who are taught using Computer
Based Communication. A
2
B
2
: The mean score of writing test of students having low learning motivation who are taught using textbook
D. Subject of the Research
1. Population
Tuckman 1972: 227 defines population as a group about which the researcher is motivationed in gaining information and
drawing conclusion. Minewhile, Sugiyono 2008: 61 states that the population is generalized area which consist of object or subject
having specific characteristics and qualifications. The population of the research is the Grade XI students of SMAN 5 Yogyakarta in the
20152016 academic year. Each class consists of 28 to 30 students. The total number of the population is 174 students divided into 6
classes. 2.
Sample The sample refers to a representative group from the
population to serve as respondents Tuckman, 2008: 226. Meanwhile, Sutrisno 2000: 182 defines sample as part of the
65
population. By using cluster random sampling, two classes are selected as samples of the research.
3. Sampling
Sampling is the way to get sample. The writer used cluster random sampling to get the sample. Cluster random sampling is the
selection of groups or clusters, of subjects rather than individuals Fraenkel and Wallen, 1993: 84. The writer used cluster random
sampling because it had some advantages, such as: it used when it is difficult or impossible to select a random sample of individuals,
it is often far easier to implement in schools, and it is frequently less time consuming Fraenkel and Wallen, 1993: 139.
The steps in cluster random sampling are: a. Define the population
b. List all classes of the population c. Select the sample by employing a procedure where sheer chance
determines which classes on the list are drawn for the sample. In this opportunity, the writer used lottery. The procedures of
randomizing sample by lottery are: a. Making a list of all classes.
b. Writing the name of each class on pieces of paper. c. Rolling the pieces of paper and, then putting them into a can and
shaking the can well.
