2. Reliability of The Test
Reliability shows that an instrument can be trusted to be used as a tool of data collecting technique when the instrument is good enough.
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It means that a test is reliable if the test is able to give constant result even though the test given repeatedly
to the same individuals or sample. Furthermore, reliable instrument is an instrument which is if used to measure the same object for some time will result same data.
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To get the reliability of the test, the researcher used inter-rater reliability, they are two
raters: English teacher and the researcher. To estimate the reliability of the test, the researcher used rank order correlation as follows:
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Note: ρ
= The number of rank order correlation Rho 6 1 = Constant number
D = Difference of rank correlation D = R1 – R2
N = The number of students.
Furthermore, to know the degree or the level of the reliability of writing test theresearcher also uses the criteria of reliability as follows:
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SuharsimiArikunto, Procedure PenelitianSatuanPendekatanPraktekJakarta: RhinekaCipta, 2010, p.142.
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Sugiyono, Op.Cit.p.17.
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AnasSudjono, PengantarStatistikPendidikanJakarta: Raja GrafindoPersada, 2008, p.232.
Table 6 Criteria of Reliability
0.800-1.000 Very high reliability
0.600-0.800 High reliability
0.400-0.600 Fair reliability
0.200-0.400 Low reliability
0.00-0.200 Very low reliability
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After calculating the reliability, the researcher found that the Cronbanch’s alpha of reliability in was pre-test was 0.982 and reliability in post-test was 0.938. The
researcher concluded that the degree of the level of reliability of the students’ was
very high and sufficiently reliable. see Appendix 10 until Appendix 15
3. Readability of the Test
Readability tests were indicators that measure how easy a documents is to read and understand. For evaluators, readability statistics can be solid predictors of the
language difficulty level of particular documents. The essential information in an evaluation document should be easily understandable. To know readability of the
procedure test instrument, the writer followed Kouame’s research. The students asked to evaluate instructions of the test and the understandability of each item on a scale of
1 to 10, where, 1 describes an item that is easy to read and describes an item that is
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SuharsimiArikunto, ProsedurPenelitianSuatuPendekatanPraktik, Jakarta: RinekaCipta, 2006, p.311
difficult to read. The questions tested individually the questionnaire for readability is
attached.see Appendix 4
J. Data Analysis 1. Normality Test
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