Hello,
I would like to know the diffrence between 2 commands : cor_auto (from qgraph
package) and lavCor (from lavaan package) to compute a polychoric correlation
matrix in order to do a network analysis.
I have the responses to the SF-36 questionnaire (36 items with ordered
responses) and I would like to have a polychoric correlation matrix by
following the Sacha Epskamp's method. But I have a warning if using cor_auto :
"Correlation matrix is not positive definite. Finding nearest positive definite
matrix". I can ignore this warning or not ? Because I try to do a polychoric
matrix in STATA software and I do not have a warning message.
And I don't understand the difference between lavCor command, because When I
use lavCor, I do not have the warning message either.
//cor.auto1 <- cor_auto(Data_1it)
//cor.lav1<-lavCor(Data_1it, ordered=names(Data_1it))
Thank you in advance for your answer.
Line
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.
