If the correlation between half-tests of a 12-item test is 0.65, how many items will be...

Question

Question

If the correlation between half-tests of a 12-item test is 0.65, how many items will be needed for the test to have a reliability of 0.8?

Answer 1

Answer #1

From the given data:

Total number of samples n = 12

Half test correlation = 0.65

Number of items will be needed for the test to have a reliability of 0.8 is,

X * 0.80 = 12

Thus, X = 12 / 0.80

X = 15

15 items will be needed for the test to have a reliability of 0.8.

Answer 2

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