Percentage of explained common varian...
Message/Author
 Meredith Thompson Knight posted on Monday, April 21, 2014 - 10:42 am
I have used EFA with geomin rotation on a sample of 319 respondents.

I am in a similar situation to many of the people who have posted on this thread. A reviewer has asked me for the percent of variance explained. I have reviewed every post, and I understand that % variance explained is a measure for PCA, not EFA, and that the goal of EFA is to reproduce the correlation matrix.

In doing some reading about summarizing and reporting EFA, I found a citation that suggests that the percentage of explained variance can serve as a means of assessing how much the correlation matrix is reproduced.

The citation can be found here:

Lorenzo-Seva, U. (2013). How to report the percentage of explained common variance in exploratory factor analysis. Technical Report. Department of Psychology, Universitat Rovira i Virgili, Tarragona.
Document available at: http://psico.fcep.urv.cat/utilitats/factor/

I have two questions:

1. Is reporting the percentage of explained common variance a reasonable way to summarize a oblique rotation? (In the working paper, Lorenzo-Seva uses Varimax)

2. Is there a way to calculate the percentage of explained common variance in MPlus?

Thanks for your help with this!

Meredith
 Linda K. Muthen posted on Tuesday, April 22, 2014 - 10:01 am
With an orthogonal rotation, you can sum the squared factors loadings and divide by the number of factor indicators. There is no option for this in Mplus.
 Shirley  posted on Friday, June 02, 2017 - 3:11 am
Dear Dr. Muthen,
I have a survey of 12 items on 3 scales. As a few of the items are positively worded, I fit a CFA with 3 trait factors and 1 method factor (as shown below). The 3-trait-1-method model fit significantly better than the original 3-trait-factor model and had better fit statistics (e.g., RMSEA). As the original 3-trait-factor model provides acceptable fit and is the hypothesis, I am interested to examine the impact of this method factor (similar to the idea of ECV in the previous post). In the CFA context, may I check if the following equation is appropriate?

(% of variance in the data the method factor accounts for)=(sum of the squared STDYX loadings on the 3 trait factors from all 12 items)/((sum of the squared STDYX loadings on the 3 trait factors from all 12 items)+(sum of the squared STDYX loadings on the method factor from the 4 cross-loading items))?

Thanks!
*********************************
VARIABLE:
[omitted]
CATEGORICAL=q1-q12;
CLUSTER=teacher;
ANALYSIS:
TYPE=COMPLEX;
MODEL:
f1 by q1* q2-q4;
f2 by q5* q6-q8;
f3 by q9* q10-q12;
Method by q1* q2 q5 q11;
f1-Method@1;
Method WITH f1-f3@0;
 Bengt O. Muthen posted on Friday, June 02, 2017 - 1:58 pm