Question

Tom wants to use a computer program to assess the reliability of his new intelligence test. The test has 10 items, and the computer program finds the average of all possible split-half correlations between groups of 5 items. What measure of reliability did he use?

Answer 1

Answer:Cronbach's alpha

Explanation:

Cronbach's alpha is used to measure consistency interms of how closely associated items in a group are.

It measures the scale of reliability as a coefficient of reliability not statistically.

below is a formula that is used to calculate this reliability.

α=N¯c/¯v+(N−1)¯c

Here N  equate to the number of items, ¯c is the average inter-item covariance among the items and ¯v equals the average variance.

The increase number of items will increase Cronbanch's Alpha.

Additionally, if the average inter-item correlation is low, alpha will be low.