Vocabulary comprehension from pre-test up to posttest score in cycle 1 and cycle 2. In analyzing that, the researcher uses the formula:
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P : percentage of students’ improvement y : pre-test result
y1 : post-test 1
P : percentage of students’ improvement y : pre-test result
y2 : post-test 2
M. Trustworthiness of Research
To analyze the examined test items, the researcher implements the trustworthiness of the test. There are some phases including:
1. Validity of Data
Validity is one of the essential requirements of good educational testing which can represent an acceptable action research. In other words validity is
the most requirements for instrument of evaluation. Arthur Hughes stated that “a test is said to be valid if it accurately what it is intended to measure”.
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It means that a test can be said valid if the test measures what it will be
measured. Terminologically, in Indonesia “valid” is “shahih”. Validity is not an absolute feature from technique evaluation. It is a relative feature for a
purpose which will be reached by the test maker. Validity should be determined by the purpose will be reached by using test. Therefore validity
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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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Arthur Hughes, Testing for Language Teachers second edition, Cambridge: Cambridge University Press, 1989, p.26.
y2 - y P =
─── X 100 y
refers to extent to which the results of an evaluation procedure serve the particular uses for which they are intended.
In thi s research the researcher adopts Anderson, Herr, and Nihlen’s
criteria that mention that validity of action research including democratic
validity, outcome validity, process validity, catalytic validity, and dialogic validity.
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In this research she uses three kinds of validity are outcome, process, and dialogic validity. First, outcome validity requires that the action
emerging from a particular research leads to the successful resolution of the problem that was being studied, that is, your research can be considered valid
of you learn something that can be applied to the subsequent research cycle.
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Second, process validity is “the validity that requires a research has been conducted in a “dependable” and competent“manner”.
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The last, dialogic validity; “it involves having a critical conversation with peers about research
finding and practices.”
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It could be concluded from the explanation above that we could be seen the outcome validity from the students’ result of the test. Moreover, in
process validity the researcher notes all events happening during the CAR. Therefore, in these validities the research is said successful if the result of
cycle II is better than cycle 1. Besides, if there might have some mistakes in the method of teaching, so the researcher should discuss this problem with
the teacher to modify the further strategies. Then, for dialogic validity, to avoid invalid data the researcher and the teacher discuss and assess the
students’ test result of two cycles.
2. Discriminating Power
