Behavioral Genetics Models

Question about Confidence Interval for Standardized path coefficients (multivariate model)
Hi everyone, I am new here and learning OpenMX. I have a problem of getting confidence interval for standardized path coefficients. Could anyone please provide me the OpenMx language about this? I also provide my scripts below and hope someone can let me know what the problem is (the script about 'ciACE <- mxCI("VC[1:5, 16:30]")' ) or how to read the output about standardized CI.
# Load Data
nl <- read.csv(file="C:/R/TwinPairACE.csv", header=TRUE, sep=",")

Fit tests for ACE models
Good morning,
I am running an ACE model for an ordered categorical outcome using script adapted from [Maes](http://ibg.colorado.edu/cdrom2016/maes/UnivariateAnalysis/one/oneACEo.R). I seem to be able to generate most indicators of model fit, including AIC, BIC, -2LL and p-values associated with likelihood-ratio tests for nested models. However, I cannot seem to generate an associated chi-square value. Is there a simple way to generate chi-square value for these tests? Thanks,
Chance
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Adding covariates to Cholesky script
Hi there, I am a new PhD student working on a project with twins for the first time. I've been provided with some older scripts from past students and some example code from a twin analysis workshop in Queensland that I haven't been able to attend yet (which I believe was run by Sarah Medland).
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Sex Limitation Model Question
Hi,
I attended the Boulder workshop a couple years ago and am now trying my hand at sex limitation modeling. Currently, I am working on a same-sex twin pair sex limitation model for liability to alcohol use disorder. I've found measurement invariance and A and C are invariant. C was non-sig. and is constrained to zero. The AUD factor intercept is invariant. Can I interpret the sex difference in the AUD means in terms of greater genetic risk for AUD in the males?
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ACE including non-twin siblings
Dear all,
I'm trying to adapt ACE heritability model to include both twins and their non-twin siblings. The data used for the analysis are imaging-derived phenotypes from the human connectome project (HCP) which includes both MZ and DZ twin pairs as well as their non-twin siblings for a subset of twins. Would be really helpful if anyone could answer a few questions.
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Multivariate cholesky model
Hi,
I have a dataset of twins on 4 time-points. I can fit the Multivariate cholesky decompositon model with ACE components. It considers unstrcutured covariance matrices for A, C and E component. I was wondering if its possible to restrict it to a special structure? Like, say compound symmetric or AR1.
Thanks
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Different age (covariate) for siblings
Dear all,
I’m working on the bivariate ACE model from 2016 Boulder workshop from Hermione Maes ‘twoSATja’ and ‘twoACEja’ (http://ibg.colorado.edu/cdrom2016/maes/UnivariateAnalysis/scriptsOpenMx.shtml). I use questionnaire data and some participants filled this out one or two years later than their twin siblings, this means that some siblings differ in age. How do I adjust the model to allow different ages between twins? I keep running into problems with non-conforming arrays…
Below the parts of the script that I have trouble adapting:
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Latent Growth Model and distal outcome
Hi,
I would like to fit the twin model in the enclosed figure, but I am not sure if this is feasible.
Can someone help me understanding if the model is identified?
In case, are there any exemples of R code for this model?
Thanks a lot
M
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