Analysis Techniques in Main Field Testing

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3. Analysis Techniques in Main Field Testing

In this step, the writer distributed tests and questionnaires. To analyze close-form questions from questionnaire, the writer applied the interpretation of the degree of agreement formulated by Best 1970: 179 as in Preliminary Product Verification. Meanwhile, to analyze the multiple-choice items, the writer obtained the data from the students’ answer-sheets. The data presented in the table as follow: Table 3.6: The Data Collection from Students’ Answer Sheets Students Items Score 1 2 3 4 5 6 7 8 9 10 11 12 Etc. Stud 1 Stud 2 Etc. Total option Opt. A Opt. B Opt. C Opt. D Opt. E In order to analyze the multiple-choice items, the writer applied IF, ID, and B-Index. According to Brown 2005: 66-83, the formulas for those analyses are showed as following: The Item Facility IF formula is: IF = N correct N total Notes: N correct = the number of students answering the item correctly N total = total number of students taking the test IF range between 0.15 -0.85 means the test is appropriate. 0.15 IF 0.85 means the test is not appropriate. 63 The data was organized in the following table: Table 3.7: The Data Collection on Item Facility IF Item Option N correct N total IF A B C D E 1 2 Etc. In line with Brown 2004:59, ID that has high discriminating power would approach a perfect 1.0, and no discriminating power would be 0.0. The Item Discrimination ID formula is: ID = high group correct – low group correct ½ X total test takers The data will be organized in the following table: Table 3.8: The Data Collection on Item Discrimination ID Item The number of students answer correctly ½ Total students ID High-ability group Low-ability group 1 2 Etc. Meanwhile, B-Index was aimed to find which item that effectively differentiated students who passed and failed the test. The range of resulting B- Index is from -1.00 to +1.00. B-Index +1.00 means that the item maximally separates the students who passed the test from the students who failed it. B- Index -1.00 shows the opposite situation. Meanwhile, B-Index which closes to 0.00 indicates that the item does not distinguish very well students who passed the test from the students who failed it. 64 The B-Index formula is: B-Index = IF pass – IF fail Notes: B-Index = difference in IF between students who passed and failed IF pass = item facility for students who passed the test IF fail = item facility for students who failed the test The data will be organized in the following table: Table 3.9: The Data Collection on B-Index Item The number of students answer correctly IF B-Index Passed group Failed group Passed Failed 1 2 Etc.

F. Research Procedure