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The improvement score of students’ vocabulary from pre-test up to students’ average score in cycle 1 and cycle 2 can be analyze by using this
formula:
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� = −
P : percentage of students’ improvement
y : pre-test result
y
1
: post-test 1
� = −
P : percentage of students’ improvement
y : pre-test result
y
2
: post-test 2 Meanwhile, in analyzing data to get the percentage of questionnaire
result, she uses formula:
= �
n = number of students who answered the option N = number of all students in the class
The analysis qualitative data used in this study is the observation of students’ and teacher’s activities during teaching learning process through
observational notes and the interview before and after CAR. In this case, the writer collected the entire data which have gained.
I. Trustworthiness of the Study
The writer applies four steps to analyze the examined test item. They are:
1. Validity
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Validity is one of the essential requirements of good educational testing which can represent an acceptable of an action research. According to Gronlund,
validity refers to the extent which the result of an evaluation procedure serves the
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David E. Meltzer, The Relationship between Mathematics Preparation and Conceptual Learning Gains in Physics: A Possible Hidden Variable in Diagnostic Pretest Scores, Iowa:
Department of Physics and Astronomy, 2008, p. 3.
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See Appendix 5, 8, 1, and 2.
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particular uses for which they are intended. If the results are to be used to describe pupil achievement, we should like them to represent all aspects of the
achievement we wish to describe, and to represent nothing else.
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T he writer adopts Anderson, Herr, and Nihlen’s criteria regarding validity
in action research, that mention the validity of action research including democratic validity, outcome validity, process validity, catalytic validity, and
dialogic validity.
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In this study, the writer uses outcome, process, and dialogic validity. Anderson defines outcome validity requires the action emerging from a
particular study leads to the successful resolution of the problem that was being studied, that is, your study can be considered valid of you learn something that
can be applied to the subsequent research cycle.
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Based on the explanation above, the outcome validity could be seen from the result of the test. When the result of cycle two is better than cycle one, it
means that the study is successful. Then, Process validity is “the validity that requires a study has
been conducted in a “dependable” and “competent” manner.”
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It could be seen from the outcome of observation. In this case, the collaborator notes all events happening during the CAR. When there might have
some mistakes in the method of teaching, then the writer discusses with the teacher to modify the further strategies. Next, the dialogic validity; “it involves
having a critical conversation with peers about research findings and practices.”
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In this case, the writer and the teacher discuss and assess the students’ test result
of cycle one and cycle two together. It is done in order to avoid invalid data.
2. Discriminating Power
