Alistair,
> >I have worked through the examples. They work because the covmat >were produced by the cov.wt which provides output as a list object. >I am trying to construct my own list object to use as the covmat. >There are no obvious instructions on how to do this. > >So, here is what I have done so far. > >I reconstructed the covariance matrix in the example and created a dataframe: > > > testmatrix > general picture blocks maze reading vocab >1 24.641 5.991 33.520 6.023 20.755 29.701 >2 5.991 6.700 18.137 1.782 4.936 7.204 >3 33.520 18.137 149.831 19.424 31.430 50.753 >4 6.023 1.782 19.424 12.711 4.757 9.075 >5 20.755 4.936 31.430 4.757 52.604 66.762 >6 29.701 7.204 50.753 9.075 66.762 135.292 > >and then used this to construct a list object like the output from >the example; > >> tstcov<- list(cov=testmatrix, center=c(0,0,0,0,0), n.obs=112) > >I tested to see whether my list object looked like the examples > >> tstcov >$cov > general picture blocks maze reading vocab >1 24.641 5.991 33.520 6.023 20.755 29.701 >2 5.991 6.700 18.137 1.782 4.936 7.204 >3 33.520 18.137 149.831 19.424 31.430 50.753 >4 6.023 1.782 19.424 12.711 4.757 9.075 >5 20.755 4.936 31.430 4.757 52.604 66.762 >6 29.701 7.204 50.753 9.075 66.762 135.292 > >$centers >[1] 0 0 0 0 0 > >$n.obs >[1] 112 > >It looks the same. So I then used this list as the argument in >factanal and get the error message. > >> factanal(factors=2, covmat=tstcov, rotation="varimax") >Error in sqrt(diag(cv)) : Non-numeric argument to mathematical function > >I know that what you see of a list is not necessarily all that is >there. So, I figure I am missing some part of the object that makes >this list suitable for use by factanal. > So, I hope this is enough detail. Any thoughts would be appreciated. >-- >Dr Alistair Campbell, PhD >Senior Lecturer in Clinical Psychology >School of Psychology >James Cook University Townsville Queensland Australia The call to factanal requires you to specify that you have a covariance matrix (covmat). Using your matrix and specifying two factors: test.df general picture blocks maze reading vocab 1 24.641 5.991 33.520 6.023 20.755 29.701 2 5.991 6.700 18.137 1.782 4.936 7.204 3 33.520 18.137 149.831 19.424 31.430 50.753 4 6.023 1.782 19.424 12.711 4.757 9.075 5 20.755 4.936 31.430 4.757 52.604 66.762 6 29.701 7.204 50.753 9.075 66.762 135.292 > test.mat <- as.matrix(test.df) > tf <- factanal(factors=2,covmat=test.mat) > tf Call: factanal(factors = 2, covmat = test.mat) Uniquenesses: general picture blocks maze reading vocab 0.455 0.589 0.218 0.769 0.052 0.334 Loadings: Factor1 Factor2 1 0.499 0.543 2 0.156 0.622 3 0.206 0.860 4 0.109 0.468 5 0.956 0.182 6 0.785 0.225 Factor1 Factor2 SS loadings 1.858 1.724 Proportion Var 0.310 0.287 Cumulative Var 0.310 0.597 The degrees of freedom for the model is 4 and the fit was 0.0572 Bill > -- William Revelle http://pmc.psych.northwestern.edu/revelle.html Professor http://personality-project.org/personality.html Department of Psychology http://www.wcas.northwestern.edu/psych/ Northwestern University http://www.northwestern.edu/ ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.