Cronbach’s Alpha

Question 1

Name two alternative definitions for Cronbach’s Alpha

Answer 1

1. The mean of all split-half reliabilities
   2.Measure of first-factor saturation

Question 2

Is Cronbach’s Alpha = the means of all split-half reliabilities ?

Answer 2

No, it is similar but not the same

Question 3

Cronbach’s Alpha deals with ______

Answer 3

Variance and Covariance

Question 4

What is meant by covariance ?

Answer 4

The amount by which items vary together

Question 5

Standardized Item Alpha deals with ________

Answer 5

Inter-item correlations and sum of the correlation matrix of each item with each other

Question 6

Why is Cronbach’s Alpha not equal to the mean of all Split-Half reliabilities ?

Answer 6

Cronbach’s Alpha is calculated by using inter-item variance and Covariance. Split-half reliability relies on covariance which Alpha measures. Cronbach’s Alpha also measures variance, which is not taken into account when when you do correlation. Cronbach’s Alpha also takes measurement error into account, and therefore reduces its score. Therefore, Cronbach’s Alpha will be smaller than than the mean of all split-half reliabilities

Question 7

What is First-factor saturation ?

Answer 7

The extent to which one factor is present in a test

Question 8

There is a misconception that CA measures ________

Answer 8

First-factor saturation

Question 9

What affects CA ?

Answer 9

Bad/poor items
Number of items
Multidimensionality