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THE EFFECTIVENESS OF CONTEXTUAL TEACHING AND LEARNING IN IMPROVING STUDENTS’ READ ING SKILL IN PROCED URAL TEXT
Universitas Pendidikan Indonesia |
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between the value 0.30 and 0.70, and were categorized as moderate. Only 1 item was categorized as difficult, since the value was below 0.30.
3.5.1.3 D is crimination Inde x
Discrimination Index aims to differentiate students who have high ability and
low ability Sudjana, 2009, p. 141. It means that if the students can answer the question correctly, it indicates that they have high ability. On the contrary, if students
give the wrong answer, it means that they have low ability. Therefore, it is expected that the students who have high ability would select the correct answer more often
that those who have low ability. To calculate the Discrimination Index, SPSS 17.0 for windows was employed. The following criteria were used to interpret the
discrimination index.
Table 3.4 The Interpretation of Discrimination Index Discrimination Index
Interpretation
DI 0.70 Excellent can be used
0.40 DI 0.70 Good can be used
0.20 DI 0.40 Moderate
DI 0.20 Poor
Sumarna 2004, p. 31
The calculation of discrimination index found that 7 items were above the value 0.7. Therefore, these items could be categorized as excellent. Whereas, 20 items
were categorized as good since the values were between 0.4 and 0.7. The rest 4 items were categorized as moderate since the values were between 0.2 and 0.4.
3.5.1.4 R e liability
According to Hatch and Farhady 1982, p. 244, reliability is defined as the extent to which a test produces consistent results when administered under similar
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Khaefiatunnisa, 2015
THE EFFECTIVENESS OF CONTEXTUAL TEACHING AND LEARNING IN IMPROVING STUDENTS’ READ ING SKILL IN PROCED URAL TEXT
Universitas Pendidikan Indonesia |
repository.upi.edu |
perpustakaan.upi.edu
conditions. Therefore, a reliable test will have consistent score if it is given more than one time toward the same object.
SPSS 17.0 for windows was applied to calculate the reliability of the test items. To determine the reliability of the test instrument, Sugiyono 2012, p. 184
states that an instrument is reliable if the minimum coefficient of reliability is 0.60. Therefore, it can be concluded that the instrument is reliable if α 0.60, while the
instrumen t is not reliable if α 0.60.
The data obtained from the calculation showed the value 0.883. By comparing the value obtained from the calculation with the minimum coefficient of reliability, it
was found that the test items were reliable.
3.5.2 Pretest and Posttest Data Analysis
