omega vs. alpha explanation
Advice: Do not post here. This does not appear to be an R question. Post to a statistics list like stats.stackexchange.com instead. -- Bert
On Wed, Oct 10, 2012 at 6:42 AM, codec cat <v.codecat at gmail.com> wrote:
Dear all I wonder if someone can explain what is the main difference between omega and alpha reliabilities? I understand an omega reliability is based on hierarchical factor model as shown in this graph<http://rgm2.lab.nig.ac.jp/RGM_results/psych:omega.graph/omega.graph_002_big.png>, and alpha uses average inter-item correlations. 1. What I don't understand is, in what condition, omega reliability coefficient would be higher than alpha coefficient, and vice versa? 2. Can I assume if the correlations between the subfactors and the variables are higher, the omega coefficient would also be higher (as shown in the omega graph<http://rgm2.lab.nig.ac.jp/RGM_results/psych:omega.graph/omega.graph_002_big.png> )? Any advice is appreciated! Thanks. [[alternative HTML version deleted]]
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