OpenMx General Help

MxMatrix object
(2) documentation for "MxMatrix" says that it "is an S4 class."
consider:
> unit5 <- mxMatrix(name='unit5', type='Lower', nrow=2, free=FALSE, values=1)
> class(unit5)
[1] "LowerMatrix"
attr(,"package")
[1] "OpenMx"
- Read more about MxMatrix object
- 1 comment
- Log in or register to post comments

contingency tables
greg
- Read more about contingency tables
- 3 comments
- Log in or register to post comments

MxConstraint Problem
(2) all models converged with an NPSOL inform value of 0.
- Read more about MxConstraint Problem
- 4 comments
- Log in or register to post comments

Model fails to terminate
1 - common parameter (lambda) for all manifest variables but separate thresholds (tau - eight values)
2 - common lambda but separate tau for all items in each group (96 taus)
3 - separate lambda for each group (12) and separate tau (96)
4 - separate lambda for each manifest (8) with 8 tau
- Read more about Model fails to terminate
- 5 comments
- Log in or register to post comments

MxRAMModel reduces to MxModel
I copied the factor analytic example from the OpenMx main website. When I run the model both the original and the resulting model with estimates will have the class MxRAMModel.
However, if I take the same model, add an arbitrary mean structure and mxData of type "raw", the resulting model will only have class "MxModel". To my understanding, it should still be of class MxRAMModel.
Is this a bug or a feature?
I attached my sample code.
cheers,
Andy
- Read more about MxRAMModel reduces to MxModel
- 3 comments
- Log in or register to post comments

Iteration history
Does anyone know how to view the iteration history from the optimization routine? I generally like to examine this information as I consider model fit. I searched the archives and it looks like this issue has received some attention but I could not figure out how to obtain this output.
Thanks in advance,
Rick DeShon
- Read more about Iteration history
- 1 comment
- Log in or register to post comments

numObs in Multiple Group Models
- Read more about numObs in Multiple Group Models
- 3 comments
- Log in or register to post comments

Another Strange Error Message
got the following error message after mxRun():
Error in runHelper(model, frontendStart, intervals, silent, suppressWarnings, :
BLAS/LAPACK routine 'DPOTRF' gave error code -4
to save y'all some time, turns out that i was running an old script that had an MxAlgebra object with the expression ".5 * VA" where VA was a matrix. to fix it, i just had to change this to ".5 %x% VA."
suggest you trap the DPOTRF error and return a more intelligible error message.
greg
- Read more about Another Strange Error Message
- 1 comment
- Log in or register to post comments

likelihood function for type=cov/cor
log(det(predictedCov)) + trace(observedCov %*% inverse(predictedCov))
by (numObs - 1). my understanding is that both the derivations from the multivariate normal pdf and the wishart pdf lead to this being multiplied by numObs and not (numObs - 1). (note that math/stat treatment of the wishart talks of "degrees of freedom" but the actual algebra defines this quantity as numObs).
i stand to be corrected here.
greg
- Read more about likelihood function for type=cov/cor
- 3 comments
- Log in or register to post comments

myTwinData.txt?
I am new to OpenMx and thought that I would try things out by working through some of the examples.
Does anyone know where I can get the dataset myTwinData.txt that is used in some of them?
Thankyou
Karin
- Read more about myTwinData.txt?
- 2 comments
- Log in or register to post comments
Pagination
- Previous page
- Page 16
- Next page