Third Party Software

Posted on
No user picture. noamm Joined: 10/10/2018

umxACE with summary data

Forums

Hi all,

I'm trying to do something rather simple - a univariate ACE model (using umxACE) with summary data (either correlation or covariance), but until now I used only raw data. I saw in the documentation this possibility is supported by umxACE, however, I can't seem to make it work.

I've tried several options attached below (mzCorDF - the correlation as a data frame, mzCorMatrix - the correlation (or covariance) matrix of twin 1 and twin 2 of the trait.

What kind of input the function expects for it to understand it is summary data?

Posted on
No user picture. jhl12 Joined: 12/14/2020

metaFIML to handle missing covariates

Forums

Dear Dr. Cheung and forum pannels,

This is Jihyun, a doctoral student.

I have a question about (currently) two approaches to use FIML to handle missing covariates in meta-regression.

At first, I had adopted the code in Dr. Cheung's book (2015) using RAM formulation and recently also tried to use metaFIML after it was introduced. However, I noticed that the two approaches showed pretty big differences in the results (parameter estimates and standard error estimates).

Posted on
No user picture. Jasmeet Singh Joined: 12/08/2020

Confirmatory Factor Analysis

Forums

Hello,

I am conducting a meta-analytic study to confirm the factorial structure of a scale using two-stage structural equation modelling.
The scale is having two subscales namely, burnout (BO) and secondary traumatic stress (STS), which load on a latent factor called "Compassion Fatigue". I want to confirm its factorial structure by meta-analysing the correlation coefficients across nine studies identified in the literature. The code I have written works fine for the first stage (TSSEM1) but it is showing an error for the second stage (TSSEM2).

Posted on
No user picture. lf-araujo Joined: 11/25/2020

umxCP with two latent variables that loads in only part of the indicators

Forums

Hi Tim and Mike,

This is the first time I am playing with real data, and since I understand lavaans syntax better than openMx's I decided to start with umx.

I am trying to specify a CP model with two latents, but my measured indicators represents parenting style and personality (big5), 10 variables in total. See fig 1. I think they are better conceptualized as two latents that can correlate, but only loads in part of the variables, the five personality traits and the five parenting styles.

Posted on
Picture of user. KevinMKorous Joined: 12/01/2020

Diagnosing Optimization Issues

Forums

Hello,

What approaches can be taken to diagnose issues related to optimization (i.e., when OpenMX status1 is not 0 or 1 even after using the rerun() function)? I have reviewed the status codes in the OpenMX documentation and I have tried mxCheckIdentification. I have also increased extraTries and I have played around with starting values for slope coefficients. However, I am running into issues and I am not sure why so I would like to see how I can diagnose what is going on.

Posted on
No user picture. pascofearon Joined: 05/07/2013

bootstrapping indirect effects

Forums

Hi Mike,
Hope you're well. I was just wondering whether there's a simple way to bootstrap the indirect effect in metasem (tssem2 or osmasem).

Thanks,

Best wishes,

Pasco

Posted on
No user picture. Max.Escaffi Joined: 09/10/2019

Imputing correlations in metasem?

Forums

Dear all!

I have another question and I was wondering if you could enlighten me.

I want to run an analysis that has 2 independent variables, 3 mediators, and 1 outcome variable.

One of the issues that I am having is that, because of my inclusion criteria, I do not have studies that included correlations between two mediators. This means, that I cannot estimate the pooled correlation matrix hence it is impossible to run the full model.

Posted on
No user picture. hannow Joined: 10/21/2020

Missing values for impliedR() and few studies to pool

Forums

Hello everyone,

I am currently conducting TSSEM using correlation matrices from primary mediation studies. I ran into some problems during the process and hoped that someone could help me.

Posted on
No user picture. Max.Escaffi Joined: 09/10/2019

Differences between metafor and tssem1?

Forums

Hi all!
I hope everyone is well.

I was hoping someone could help me with an issue I am having. I am running a model, but first I wanted to explore the correlation matrix as you would normally do. For this, I created the correlation matrix using the metafor package. After this, I run the model using the metaSEM package, and when I checked the tssem1 results, I realised that the correlation results were very different in magnitude (significance levels did not vary).

Posted on
No user picture. ksyoung Joined: 10/06/2020

Implementing ImpliedR in TSSEM

Forums

Hello, I was hoping someone might be able to help with use of the impliedR function in the context of a TSSEM model. I am conducting a 2-stage SEM following the Cheung guide here: https://cran.r-project.org/web/packages/metaSEM/vignettes/Examples.html#two-stage-structural-equation-modeling-tssem