instrument before it is applied to the sample of this research. The writer made test consist of 50 numbers in type of multiple choice. The writer tested the instrument
to the students in the same school but not to students as the sample. In this case, X MIA 3 and X MIA 4 were choosen as sample of the research while the test was
tested to X MIA 2 class of SMAN 1 Kota Tangerang Selatan. The writer applies four steps to analyze the examined test item. They are:
1. Validity
Validity is important to know whether the test is valid or not. According to Arikunto, a test is valid if it measures what it purposes to measure.
8
To test the validity of the instrument, the writer
used “ANATEST” software version 4.0.9 developed by Drs. Karno To, M.Pd. and Yudi Wibisono, ST. After the calculation
using “ANATEST”, the writer found from 50 questions that were given, there are 19 questions which are valid and then the writer revised 6 questions to make it
became 25 questions.
2. Reliability
Reliability is whether an instrument produced consistent result. According to Arikunto, test is reliable if it provides consistent and stable characteristic.
9
To find out the realiability of the instrument
, the writer used “ANATEST” software version 4.0.9 developed by Drs. Karno To, M.Pd. and Yudi Wibisono, ST.
The criterion of reliability:
10
= 0,91 – 1,00 = very high
= 0,71 – 0,90 = high
= 0,41 – 0,70 = enough
= 0,21 – 0,40 = low
= 0,21 = very low
8
Suharsimi Arikunto, Dasar-Dasar Evaluasi Pendidikan, Jakarta: Bumi Aksara, 2003, p. 65.
9
Ibid., p. 89.
10
Ibid., p. 102.
From the calculation using “ANATEST”, the reliability score that the writer get is 0.73. It means the test is reliable and categorized into high reliability.
3. Discriminating Power
The discriminating power of a test item is the ability of test item to discriminate between students with high and low achievement.
11
the formula used to analyze discriminating power:
⁄ D
= Discriminating Power R
U
= Number of pupils in the upper group who got the item right R
L
= Number of pupils in the lower group who got the item right T
= Number of pupils included in the item analysis. The scale of the discriminating power:
12
DP =
= Used DP
= = Revised
DP =
= Discarded However, the writer used “ANATEST” to analyze the discriminating power
of test item used in this study.
4. Item Difficulty
According to Arikunto, item difficulty is to identify whether a test item is categorized into difficult or easy in a test. The formula used to find out difficulty
index as follow:
13
Explanation: P = Item Difficulty
B = The Number of Pupil who got the item right JS = The total number of pupil who tried the item
11
Ibid., p. 211.
12
J. B. Heaton, Classroom Testing, New York: Longman Inc, 1990, p. 174.
13
Arikunto, op cit., p. 208
