OpenSEM Forums

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No user picture. JuanJMV Joined: 07/20/2016

Multivariate ACE-ADE model

Hello,

I am trying to fit a 5-variate model. But I am not sure about the best way to do it.

I have got these results from the univariate analyses

VAR1
ADE 0.34 0.10 0.57
AE 0.42 * 0.58

VAR2
ADE 0.26 0.16 0.58
AE 0.41 * 0.59

VAR3
ACE 0.29 0.13 0.58
AE 0.45 * 0.55
CE * 0.33 0.67

VAR4
ADE 0.23 0.17 0.59
AE 0.39 * 0.61

Posted on
No user picture. diana Joined: 04/17/2019

Why mxTryHardOrdinal()dosen't report start values?

Hi, everyone!
When i useSatFit <- mxTryHardOrdinal(SatModel, intervals=TRUE,extraTries = 15,finetuneGradient=FALSE,bestInitsOutput=TRUE) ,the result is Solution found! Final fit=22505.957 (started at 22819.562) (16 attempt(s): 16 valid, 0 errors). I don't know why it dosen't report start values from the best fit.

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No user picture. diana Joined: 04/17/2019

saturated univariate SEM model of a binary variable

Dear all,
I have some problems of fitting saturated univariate SEM model of a binary variable "whtr_g". I would appreciate it if anyone could help me.
1. I always get warning message when fitting saturated SEM model(see warning message.png), whether using SLSQP, NPSOL or CSOLNP optimizer. What’ more, the result of three optimizers are different. But I don’t know if there are errors in my code. Please help me to check it.

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No user picture. yaning Joined: 04/12/2019

How to calculate bivariate h2(or c2, e2) in bivaraite SEM model with two binary traits?

Hi,
I have encountered several problems in doing bivariate SEM models, which is an important part of my graduation project.The main problems are as follows:

Posted on
No user picture. Aivil Joined: 03/14/2019
Posted on
No user picture. Aivil Joined: 03/14/2019

How to implement FIML estimation in OpenMx?

Hello,
I am running this code to conduct LGCM prior to GMM.
I was wondering if there is a way of implementing FIML instead of ML in my code.

This is because my data has a lot of missingness by design (longitudinal data) and is not normally distributed.

Many thanks!!!

require(OpenMx)

?MxFitFunction
fitFunction <- mxFitFunctionML(rowDiagnostics=TRUE)
mxOption(NULL,"Default optimizer","SLSQP") ### to avoid msg error: https://openmx.ssri.psu.edu/node/4238

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No user picture. Aivil Joined: 03/14/2019

3-class Mixture Model : Help to find Starting Values for each class!!

Hello,

I am currently try to fit a 3-class mixture model on longitudinal data. I'm having a hard time understanding how I should set the starting values for each class.

As far as I understood from Chapter 7 of "Growth Modeling" (Grimm, Ram & Estabrook, 2017), p.150, starting values should be different for each class.

I have tried using the mxTryHard() function to set the best fitting starting values, but it seems there is no difference in the outputs with or without that function.

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No user picture. Aivil Joined: 03/14/2019

Associative Growth Mixture Model in OpenMx

Hello,

Is it currently possible to implement an Associative Growth Mixture Model in OpenMx? I was having a look at this paper from Hix-Small et al. (2004) where the authors are combining a multivariate LGM and a GMM to simultaneously
study the relationships among alcohol and marijuana use over time and investigate the existence of sub-populations.

I will probably need this approach to analyze my data, so just wondering if there is an alternative to Mplus.

Thanks

Posted on
No user picture. Aivil Joined: 03/14/2019

Associative Growth Mixture Model in OpenMx

Hello,

Is it currently possible to implement an Associative Growth Mixture Model in OpenMx? I was having a look at this paper from Hix-Small et al. (2004) where the authors are combining a multivariate LGM and a GMM to simultaneously
study the relationships among alcohol and marijuana use over time and investigate the existence of sub-populations.

I will probably need this approach to analyze my data, so just wondering if there is an alternative to Mplus.

Thanks