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Behavioral Genetics Models

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

Common and independent models

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Behavioral Genetics Models
Hello,

I am trying to fit a trivariate model with 3 continuous variables. I am also trying to fit the independent and common pathways models but I do not know if my script is correct.

My models have:
ADE: 27 parameters
Independent pathway model: 27 parameters
Common pathway model: 24 parameters

I think that number of parameters is correct but I am not sure. Also, I have negative values (for example dl_1_1, fl_2_1) and I do not know if it is correct.

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No user picture. Kelsey Joined: 01/31/2017

Bivariate model with binary and continuous variable

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Behavioral Genetics Models
Hi,
I am new to bivariate models and I have tried to adapt the twoACEj.R script by Hermine Maes from an ordinal to a binary variable in the below script. The script runs without errors, but my first question is whether my adaptations are correct?

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

phenotypic correlation

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Behavioral Genetics Models
Hello,

I am a little bit confused about how to calculate the phenotypic correlation between variable 1 and variable 2, in a bivariate model with one binary variable and one continuous variable.

I mean if I use this: mxEval(cov2cor(V), fitADE, T). I get a value of 0.200 whereas if I calculate the correlation in SPSS (also in R) I get a value of 0.150.

I do not know if I am doing something wrong. Should the results be the same right?
I have tried with different methods, with and without covariables etc… But I get the same value.

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Picture of user. Julia Joined: 03/29/2012

System is exactly singular

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Behavioral Genetics Models
Hi all,

I am running a trivariate Cholesky ADE model with one binary and two continuous variables. As profile-based confidence intervals took more than 24h to run and a lot of them were missing I decided to try bootstrapping. I ran mxBootstrap with 1000 replicates to get 95% CI and all looked fine except CI's for dominant genetic correlation rD. I get the following error:

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

Siblings

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Behavioral Genetics Models
Hello,

I am trying to do a univariate analysis with a binary variable. I am not sure how to treat siblings
I have created different groups MZ, DZ, SIB (which I think is the same as introduce SIB in the DZ group).

I have also checked if DZ and SIB can be equated through the saturated model and there are not significant differences when I equated means and variances between DZ and Sib

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No user picture. szellers Joined: 04/04/2018

Standardizing factor loadings

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Behavioral Genetics Models
I am working with a common path model and I am having difficulty standardizing my factor loadings. In the past, I have identified the model by constraining the variance of the latent phenotype to 1, then I standardize factor loadings by using a matrix of standard deviations (SDs on diagonal, 0s on off-diagonal) and multiplying that by the matrix of the unstandardized factor loadings (I can attach code for this if necessary)

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Picture of user. Julia Joined: 03/29/2012

Bootstrap CI's for algebras

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Behavioral Genetics Models
Hi.

Is it possible to get bootstrap confidence intervals for algebras? I am running a trivariate CHolesky decomposition model on binary variables and estimating CI's through mxCI takes more than 24h. When I ran mxBoostrap, I got CI's only for model parameters, but not for algebras. Is there a way to specify it? Or is there a way to reduce the time to running a model with intervals=T?

Thank you in advance!
Julia

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Picture of user. gary.marks@acu… Joined: 07/14/2016

Multivariate Independent Pathway with Multiple Occasions

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Behavioral Genetics Models
I have been analyzing achievement/cognitive test data from the NLSY79 Children data set. I have constructed sibling-cousin pairs for each of the five tests (PPVT, digit memory, reading comprehension, reading recognition and math) at 5 occasions (ages 5-6, 7-8, 9-10, 11-12 &13-15). I have successfully run a independent pathway model for domain scores averaged over occasions (zero to 4) and 5 separate models for each age. However, there are several reasons why a combined model using all the data is more desirable than running separate scripts for each.

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Picture of user. tbates Joined: 07/31/2009

confidence intervals in a common pathway model (with constraint)

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Behavioral Genetics Models
Reviewers have requested I give confidence intervals on estimates from a common pathway model (I am using the `umx::umxCP` function to build my common pathway model).

When I try and use Hunter's nice `mxSE(top.es_std[1,1], model = cp3)` function on to request the SE on the specific-e for variable 1), I get the following error:

Model does not have a reasonable Hessian or standard errors.
Model has at least one mxConstraint. This prevented standard error computation.
Try mxCI()

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No user picture. Aurina Joined: 01/05/2016

Including covariates to saturated model

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Behavioral Genetics Models
Hello,

I'm trying to run an ACE model for some imaging-derived measures and hope you could help me to solve some of the issues.

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