Fri, 10/16/2009 - 05:14

When I run the simple regression example with matrix specification i get

> uniRegFit <- mxRun(uniRegModel)

Running Simple Regression -- Matrix Specification

Error: The F matrix in model 'Simple Regression -- Matrix Specification' does not have column names.

I've set up some dummy data to feed into the model

x <- rnorm(40);

y <- 2* x + rnorm(length(x), sd=0.5);#

SimpleRegRaw <- data.frame(x, y)

hi mark,

Not sure which script you are running (good to give its path or a url)

if its this demo:

system.file("demo", "SimpleRegression_MatrixRaw.R", package="OpenMx")

It runs fine and doesn't have an F matrix

I think he meant from the documentation:

http://openmx.psyc.virginia.edu/docs/OpenMx/latest/Regression_Matrix.htm...

If that's not what you're running, can you copy and paste the exact code for us?

Thanks Tim and Jeff.

Jeff is right that I meant the example code in the manual. Having a look at SimpleRegression_MatrixRaw.R I see that the F matrix requires a dimnames argument.

(and also that the documentation has been updated)

I also see now that the dimnames in the Filter matrix are what hook up the rows and columns of these matrices to the manifest variables in the mxData object.

The documentation http://openmx.psyc.virginia.edu/docs/OpenMx/latest/Regression_Matrix.html was out of sync with the demos. This has been corrected in the subversion repository and online. If you were running a script from a different source, please let us know.