Can anyone explain the difference between (Macdonald's) omega hierarchical and omega total?

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Thanks for all your input?

This question is well answered now. Thanks!

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Boris Forthmann Popular answer

It is well explained here:

http://www.personality-project.org/r/book/#chapter7

The difference is mainly that omega_t gives an reliability estimate of the overall variance in the data that is due to a general factor and also specific factors. The omega_h is a reliability estimate for the variance that is due to the general factor only.

Boris Forthmann

Karin Schermelleh-Engel

Revelle and Zinbarg explain the different omega coefficients in their article:

Revelle, W. & Zinbarg, R.E. (2009). Coefficients alpha, beta, omega and the glb: comments on Sijtsma. Psychometrika, 74(1), 145-154.

Kind regards,

Karin