OpenMx Structural Equation Modeling

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No user picture. Kwabenaaaddo Joined: 02/01/2021

Help with TSSEM Problem encountered

Dear Forum (Mike),

I have been working on a TSSEM using R and encountering the error below, which I do not know how to address. I would be grateful if you could help me proceed with your suggestions and diagnosis. I have attached the data and R codes for your perusal. 

Thank you so much for your help in advance.

Regards,

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No user picture. cffalk2 Joined: 10/06/2025

mxComputePenaltySearch

Happy to see this implemented (thank you!). Questions about how it works. I've seen the vignette here: https://cran.r-project.org/web/packages/OpenMx/vignettes/regularization.html

But, that includes use of mxPenaltySearch. The one above (but not mxPenaltySearch) has an option to change ebicGamma, which is desired. I don't see documentation or examples for mxComputePenaltySearch, but would guess it could form part of a custom compute plan.

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No user picture. IvanVoronin Joined: 08/18/2013

Mixed effects model - matrix specification

Hello,

I am looking for advice with regard to the implementation of mixed effects model in OpenMx. 

I am starting with a simple model where one dependent variable Y is predicted by four correlated variables X1-X4. The participants in the sample are clustered in pairs (they are twins).

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No user picture. Ilaria Joined: 07/22/2024

Problems with Constrain expected Means and Variances to be equal across Twin Order

Hi all,

I am trying to fit several bivariate [between my exposure at age 16 and my outcomes at age 21 (accounting for age and sex)] and trivariate [my exposure at age 16 and my outcomes at ages 21 and 26 (also accounting for age and sex)] ACE models. However, I’ve started by fitting univariate saturated and submodels, followed by ACE and submodels, to eventually fit my bivariate models. The saturated models run fine across all, but when I try to fit the constrained models (by twin order and zygosity), I get the following error message:

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No user picture. didenursahin Joined: 03/20/2023
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No user picture. Tugce Yildiz Joined: 01/15/2024

NA CIs for Bivariate Model

Hi, I am trying to run a bivariate model with two variables and 2 covariates. However, I get NA !!! for BivA, BivC and BivE. Can you help me solve this issue?

Here is the script:

### SELECT VARIABLES HERE
data_file <- "Cerebellum_volumes.csv"
variable_input1 <- "lsas_total"
variable_input2 <- "Vermis_VII"
cov1 <- "Total_Cerebel_Vol"
cov2 <- "age"

### Import data
dat <- read.csv(file=data_file, header=TRUE, sep = ";")

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No user picture. lior abramson Joined: 07/21/2017

checking total h2 at time 2 in a longitudinal choelsky model with paths script

Hello,
I am conducting a longitudinal Cholesky model with one variable in two time points.
I use the script written below with paths.
How can I modify this script to find for the total h2 at time 2? that is, I want to find the heritability explained by both the genetic effect from time 1 and the genetic effect from time 2, and the confidence interval of this estimate.
Thank you very much for your help

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No user picture. jkraemer Joined: 12/18/2022

goodness-of-fit indices for ML SEM

I have been asked by a reviewer to offer a better justification for the fit of my proposed ML model by "indicating the fit of the within and between model separately". After reading several chapters made for MPlus, I first looked to mxRefModels(). But, I am under the impression that it does NOT work with ML SEM. So, I tied to make the saturated and independence models for within and between myself for the various calculations. I was successful regarding the independence model but not the saturated model.