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concluded of what it meant. After that, the researcher had to write down the final data in the form of qualitative descriptions.
The data from pre-test and post-test were analyzed quantitatively. There are three ways of analyzing quantitative data. The first one is to find mean which
is an average number, in this case the average of students’ writing scores. It can be calculated by adding up all scores and dividing them by the number of students
in the class. The second one is to find standard deviation and the last one is to find t-test MacKay, 2006: 43. However, the researcher decided to use the mean value
of students’ writing performance instead and found the final result by comparing the mean values from pre-test and post-test of both cycles.
G. Research Validity and Reliability
1. Validity
Validity is the quality of a measuring instrument in which the result obtained from the test really shows the actual achievement of the test takers. In
other words, a measuring tool is said to be valid if it provides the true data that indicate the intended ability one wishes to assess.
According to Burns 1999 there are five criteria of validity that have to be fulfilled in order to get the valid data in action research. Those five criteria of
validity are as follows:
a. Democratic Validity
The researcher needs to have discussions with the collaborators during the research and those collaborators are given opportunities to give ideas or
suggestions to the researcher.
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Right after the first meeting, the researcher had a discussion with the English teacher about what happened during that meeting. The teacher gave her
some suggestions especially on how to handle a big class like class VIII B. Every time the researcher had done conducting the research cycle, she
discussed the results with the teacher and the teacher advised her on her next plans. The researcher also made sure to consult the teacher about every lesson
plan and material she wanted to use in the class.
b. Outcome Validity
It is related to the notion that certain actions which are done lead to the result that is successful within the context of the research. It is fulfilled when the
indicators that show students’ improvement are formulated. After doing some library research about previous studies on this subject,
the researcher got the confidence to start this research. She had a notion that the outcome of the study would be a success. Once the actions were implemented and
the desired result the students’ writing skills improved considerably was starting
to show, outcome validity had been fulfilled.
c. Catalytic Validity
The researcher needs to allow participants, in this case the students, to understand more about social realities and how they can make changes within the
research context. Not only that, during the research process, the researcher also has the opportunities to learn more about the realities in English teaching and
learning process while the collaborators are involved in monitoring the research process.
