materials, with the student who has not been the materials. The higher coefficient discrimination index the item of question, the more capable of
item differentate between the student who have control of competence with the student who has not been or less to take control of the
competency. The formula to determine index discrimination is:
� = −
= � − �
Note: J
= amount of participant = amount of upper participant
= amount of lower participant = amount of upper participant which answering true question
= amount of lower participant which answering true question � = = proportion upper group participant which answering true
question � =
= proportion lower group participant which answering true question
Interpretation of discrimination index, that’s: 0,00
–0,19 = poor 0,20
–0,39 = enough 0,40
–0,69 = good 0,70
–1,00 = very good Suharsimi, 2009: 201
The interpretation has been modified because number in Suharsimi’s
book between the lower limit and upper limit having the same number, so makes a trouble in inserting category of question.
5. Distractor Efficiency
Distractor efficiency used to know distractor functioning properly or not. The distractor efficiency is testee distribution to specify the answers
form multiple choise. The distributions answer will be know by the
students choose a, b,c, d, e or not choose. Distractor efficiency can be determined the distractor whether working or not. The item be classified a
good question if the distractor can function well. Characteristic good distractor by marked at least 5 of the test. Knowing the percentage of
the vote testee distractor using formula as: �
= �
� ��
� ���
100
F. Data Collection Techniques
This research using two data collection techniques, they are: 1.
Interview An interview conducted by researcher to collect the data on
September 8
th
, 2014 with accounting teacher of theory vocational education in class XII of the 1
st
semester test at SMK YPKK 1 Sleman. An interview conducted to ensure a time for researcher took the data. Researcher also get
question that will be used by the teacher Accounting Theory subjects in class XII Accounting at SMK YPKK 1 Sleman.
2. Documentation
This technique is used to obtain a lattice of question, question, key of the answers, and the work sheet of 1
st
Semester Final Test of Accounting Theory for Vocational Education in Class XII Accounting at SMK YPKK
1 Sleman.
G. Research Instrument
An instrument using in this research are: 1.
A list of student name,
