Data Analysis An Item Analysis On Discriminating Power Of English Summative Test (An Observation at the Seventh Grade of SMP Al Wathoniyah 09 East Jakarta)
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One of the items has good discriminating power is an item no 9, because of 12 students from the upper group who answered the item no 9 correctly
and only 6 students from the lower group who answered the item no 9 correctly. So, the item can tell as the good item because test item can
differentiate the upper and the lower group and the discriminating power 0.46. Then, the item has satisfactory discriminating power is an item no 3,
because of 11 students from the upper group who answered the item no 3 correctly and only 7 students from the lower group who answered the item no
3 correctly. So, the item can tell as the satisfactory item because test item can differentiate the upper and the lower group and the discriminating power
0.31. Next, one of the items has poor discriminating power is an item no 1 as the poor item because test item can not differentiate the upper and the lower
group or same and the discriminating power 0.00. The last, the item has very poor discriminating power is an item no 15 because of 7 students from the
lower group who answered the item no 15 correctly rather than 5 students from the upper group who answered the item no 15 correctly. So, the item can
tell as the very poor item because the item cannot differentiate the upper and the lower group and the discriminating power -0.15 negative.
From the analysis data above, it can be conclueded that the English Summative Test at the seventh grade of SMP Al Wathoniyah 09 East Jakarta
has a good discriminating power so that the question from the summative test should be saved or can be used to next test.
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CHAPTER V CONCLUSION AND SUGGESTION