discrimination or negative discrimination power means that the item is bad. The item with negative value means that the students in the lower group perform better
than the students in the upper group. This item must be revised or discarded.
2.6 Item Difficulty
The difficulty of the test item is indicated by the percentage of students who get the item right. The more difficult items, the fewer will be the students who
select the correct option. And the easier the items are the more will be the students who select the correct one.
Teacher usually have wrong opinion, they feel that they can get respect of their students by giving them east test, and some of them giving more difficult test
items in order to get the respect from the students and parents. There are some factors in constructing the difficulty level of test items.
According to Mahren and Lehman 1984:31 the concept of difficulty or the decision of how difficult the test should be depend on a variety factors.
There are: 1
The purpose of the text 2
The ability level of the students 3
The age or grade level of the students The index of item difficulty P can be commutated by two ways. First by
dividing the number of the students who answered an item correctly R with the total number of the students tested T, and then multiplied by one hundred.
P = R X 100 T
The second way is by dividing the students into the upper group and the lower group only, and assuming the responses of the students in the middle group will
follow essentially in the same pattern The index difficulty will run from 0.00 to 1.00, with 1.00 indicating the easiest
possible item. The index of difficulty which is in the range from 0.31 to 0.70 would indicate that the item is considered moderate or acceptable. The most
difficult will run from 0.00 to 0.30. By knowing how many students who answered the item right, we can calculate
the item difficulty. It can be calculated through two ways, but in this final project the writer used the first way. That is by dividing the number of the students who
got the item right with the total number of students tested and multiplied by one hundred. By that, we can know which item is difficult, moderate, and easy.
2.7 Curriculum
