metaSEM

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Picture of user. k.corker Joined: 10/05/2015

tssem1 random effects model: diag vs. symm

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Hi Mike,

Thanks very much for your excellent metaSEM package. I have successfully wrangled my data into the necessary format and run a fixed effect model and then a random effects model with the "diag" option. The data is 37 samples (ranging in size from 28 to 1589) of 8 variables (and none of the samples have missing data; all samples provide all 28 correlations). I can't get the random effects model to run with the "Symm" option, and it is driving me nuts as to why this is the case. I get Open Mx error code 6, and all of the parameters come out NA.

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No user picture. jode Joined: 08/21/2015

Moderation analysis

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Hi metaSEM users, hi Mike,

I am just wondering if and how to apply a moderator analysis in metaSEM. Can I apply the approach you describe in your book beginning on page 170? I would like to test a moderating effect between two effect sizes by treating one variable as moderator. Or is there any other approach?

Thanks for your help.

Johannes

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No user picture. jode Joined: 08/21/2015

Mediation analysis

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Hi,
I would like to perform a mediation analysis by defining the indirect effects with mx.algebras in the wls() funktion.
I tried mx.algebras= list( ind=mxAlgebra(b410*b14, name="ind"))), where b410 and b14 refer to the paths in the A matrix. However, I get the following error in the analysis:

Error in running the mxModel:

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No user picture. jode Joined: 08/21/2015

How can I compare coefficients within a TSSEM?

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Hi metaSEM users, hi Mike,

I enjoy using the metaSEM package for my analysis in R. I amjust wondering how I can compare path cofficients in an estimated model (t-test) ? Probably it is quite easy, but I am new to R. So help is really appreciated :)

Thanks
Johannes

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Picture of user. forscher Joined: 03/05/2013

Very small standard errors from indirectEffect()

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Hi metaSEM users, hi Mike,

I've been attempting to use indirectEffect() to estimate the direct and indirect effects from a series of 3 by 3 correlation matrices. I then want to meta-analyze the resulting direct and indirect effects using either meta() from the metaSEM package or mvmeta() from the mvmeta package in R.

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No user picture. cla18@humboldt.edu Joined: 06/23/2015

Deriving Standard Errors from indirectEffect command

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I am trying to derive a standard error for standardized indirect effects but am unclear how to find their standard errors using the output below. Is there a way to calculate the SE from the information below?

x <- matrix(c(1, -0.07, -0.23, -0.07, 1, 0.35, -0.23, 0.35, 1), ncol=3)
dimnames(x) <- list( c("y", "m", "x"), c("y", "m", "x") )
indirectEffect(x, n=81, standardized = TRUE )

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No user picture. HAMED Joined: 06/15/2012

Determining R2 based on TSSEM Outputs in metaSEM

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Greetings,

I have run a random-effects TSSEM (tssem2()) in metaSEM and received the estimated path loadings and correlations among factors in the output for my structural model. I also need to find the R2 values for my endogenous variables in my structural model. I was wondering how I can determine R2 values. I think they should be calculated as 1-var of the endogenous variables found in impliedS1 matrix in mx.fit component of the tssem2() output:

random2<-tssem2(...)
random2$mx.fit$impliedS1

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No user picture. HAMED Joined: 06/15/2012

Univariate random-effects model

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Greetings,

I have tested a correlation, for which I have a small number of studies (two studies), using univariate random-effects model in metaSEM. The results (see attached) show a significant Q statistic, non-significant Tau2_1_1, and I2 of 99%. I was wondering if such results should be interpreted as a significant heterogeneity among my studies or not. In particular, how should I interpret the results when Q is significant, but Tau is not?

I appreciate any help,
Best,
/Hamed

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No user picture. Wojtek Joined: 04/04/2015

metaSEM installation problem

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Hello,

I'm having problems when trying to install the metaSEM package. I'm a Mac user and I have the R 3.1.3 (Mavericks build) version. After having installed all packages required for metaSEM (OpenMx, MASS and ellipse), when trying to install the package directly, here's what I get :

install.packages("metaSEM")
Warning message:
package 'metaSEM' is not available (as a binary package for R version 3.1.3)