class. After the result of the try out had been scored, an analysis was made to find out the validity and reliability of the try out item. All of them were used to decide
which items should be tested in making the instrument.
3.10 Try Out
Saleh 2001: 33 says that “the data of the students’ achievement cannot be collected by questionnaire”. Therefore, test is used to measure students’
achievement. The quality of the data, whether it is good or bad, is based on the instrument to collect the data. A good instrument must fulfill two important
qualifications. Those are valid and reliable. So, before the test was used as an instrument to collect the data, it had been tried out first to the students in the class.
After scoring the result of the try out, the writer made an analysis to find out the validity and reliability of the items of the test. All of them were used to decide
which items should be used in collecting the data. The arranged instrument will be tried out in another class with same grade.
From the result of tryout then analyzed to determine the questions which proper to be used in research instrument. The purpose is to know whether the test have good
requirements test or not. The data analysis that will be used in measuring tryout test involve: Validity analysis, Reliability analysis level difficulty analysis, and
discriminating power. 29
3.10.1 Validity Analysis
Test validity, that is, the relevance of the examination, is the area on which many of testing controversies have centred: objective tests are criticized for their failure
to measure this or that aspect of a subject. Validity is not measured, but interred from the evidence. The degree of test
validity is not derived from a statistical analysis of test performance, but from a meticulous analysis of the content of each item and of the test as a whole.
A threat to validity means that design issues may threaten the experiment so that reached from data may provide a false reading about probable cause and
effect between the treatment and outcome. Although threats is identified such as not having good measures or using inappropriate statistics, they are internal and
external validity. In this case, a number of types of validation are applied to the tests, they
are: 1 Content Validity
We should expect the best to be based upon a careful analysis of the skill or an outline of the course, and we would further expect the items to represent
adequately each portion of the analysis, not just those aspects which lend themselves most readily to a particular kind of test question. It may be said to
have content validity if the analysis accords with the views of recognized authorities in the skill area and the test reflects such an analysis.
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