Bookmark and Share

Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: factor analysis - calculating Crohnbach's alpha

From   "JVerkuilen (Gmail)" <>
Subject   Re: st: factor analysis - calculating Crohnbach's alpha
Date   Tue, 9 Oct 2012 18:45:33 -0400

Being one of the resident psychometricians, I can give a more complete
answer later but Cronbach's alpha for an unweighted total score in
Stata is given by -alpha-. It has quite a number of options and is
probably what you're looking for.

Principal components of the correlation matrix gives a different
reliability coefficient, Armor's theta, which is defined to be

       theta = [Q/(Q-1)] (1 - 1/maxeigenvalue)

This is the reliability coefficient corresponding to the first
principal component.

If you use factor analysis to determine weights, you can compute
McDonald's omega:

      omega = (sum of factor loadings)^2 / (sum of uniquenesses + (sum
of factor loadings)^2)

This works for both correlation and covariance matrices.
*   For searches and help try:

© Copyright 1996–2018 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   Site index