search for: sem

Hello, I have conducted an SEM in which the resultant standardized path coefficients are much higher than would be expected from the raw correlation matrix. To explore further, I stripped the model down to a simple bivariate relationship between two variables (NDVI, and species richness), where it's my understanding that the...

Hello, I use the function sem the following way sem.mod <- sem(model, mod.cov, N=109) where the variables are modelled: Z -> M Z -> I Z -> R M <-> M I <-> I R <-> R Z <-> Z The output is ... Normalized Residuals Min. 1st Qu. Median Mean 3rd Qu. Max. -7.3300 -0.2750 -0.2670 -0.1290 -0.0369...

I am new to R. I just tried to recreate in R (using sem package and the identical input data) a solution for a simple measurment model I have found before in LISREL. LISREL had no problems and converged in just 3 iterations. In sem, I got no solution, just the warning message: "Could not compute QR decomposition of Hessian. Optimization probably...

Dears, I'm a college student and In doing my statistics homework. I use R with SEM package as my tool for sem analysis, but my teacher told me AMOS is more suitable for such analysis. Could someone help tell me whether it is true that some commercial software is better accepted in academic fields? Sorry if I should not post such topics here. -- Best Regards, Reeyarn T. Lee A...

Hi experts, I just started to learn R today, and tried to work with an add-on package sem. I have a version of 2.3.1 on MacOS X 10.4.6 with sem put under /Library/Frameworks/R.framework/Versions/2.3/Resources/library However when I typed library(sem) the following error showed up: Error in library(sem) : 'sem' is not a valid package -- installed < 2.0.0? Why is this?...

Sorry if this question has been asked previously, I searched but found little. There also doesn't seem to be a dedicated SEM list-serv so hopefully this will find its way to the appropriate audience. In discussing SEM with a colleague I mentioned that a model they were fitting in AMOS was equivalent to a linear regression and that the coefficients would be the same. This of course was the case. However, the standard...

Hi there, I just saw your question on the help list and tough you could help me with some start-up info.... I just downloaded the R project software to try running SEM analysis and I also downloaded the SEM package. But it just sits there on the desktop and R does not know where it is...I can¹t figure out how to organize the files...When I type ?sem in R it says object sem not found...I can¹t seem to find help on the web on how to set-up the packages.... Well, t...

Dear R People: Could someone recommend a "baby book" on path analysis and SEM, please? Or if someone has an example that they use in the classroom setting, that would be very cool too. Thanks in advance, Sincerely, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodgess at gmail.com

Hi R-colleagues. In the sem-package i have a problem to introduce hidden variables. As a simple example I take an ordinary factor analysis. The program: cmat=c(0.14855886, 0.05774635, 0.08003300, 0.04900990, 0.05774635, 0.18042029, 0.11213013, 0.03752475, 0.08003300, 0.11213013, 0.24646337, 0.03609901,...

Hi, I would like to print elements from sem (structural equation modeling) function (e.g., model-reproduced covariance matrix (C); estimated asymptotic covariance matrix of parameter estimates (cov)). How can I do this? Thanks, Andr?? -- Andr?? Tavares Corr??a Dias Laborat??rio de Ecologia Vegetal Universidade Federal do Rio de Jan...

...gallium/drivers/nouveau/nv30/nv30_draw.c b/src/gallium/drivers/nouveau/nv30/nv30_draw.c > index a681135..03c0c70 100644 > --- a/src/gallium/drivers/nouveau/nv30/nv30_draw.c > +++ b/src/gallium/drivers/nouveau/nv30/nv30_draw.c > @@ -230,22 +230,24 @@ static const struct { > [TGSI_SEMANTIC_BCOLOR ] = { EMIT_4F, INTERP_LINEAR , 1, 3, 0x00000004 }, > [TGSI_SEMANTIC_FOG ] = { EMIT_4F, INTERP_PERSPECTIVE, 5, 5, 0x00000010 }, > [TGSI_SEMANTIC_PSIZE ] = { EMIT_1F_PSIZE, INTERP_POS , 6, 6, 0x00000020 }, > - [TGSI_SEMANTIC_GENERIC ] = { EMIT_4F, INTERP_P...

I am a new user of the function sem in package sem and lavaan for structural equation modeling 1. I don?t know what is the difference between this function and CFA function, I know that cfa for confirmatory analysis but I don?t know what is the difference between confirmatory analysis and structural equation modeling in the package...

Hi, we are trying to do structural equation modelling on R. However, one of our predictor variables is categorical (smoker/nonsmoker). Now, if we want to run the sem() command (from the sem library), we need to specify a covariance matrix (cov). However, Pearson's correlation does not work on the dichotomous variable, so instead we produced a covariance matrix using the Spearman's (or Kendalls) correlation method, which works. Running the sem() command...

Today's episode of "why is AD break", brought to you by: > [2017/09/05 10:17:06.015617, 3] ../source4/auth/gensec/gensec_gssapi.c:613(gensec_gssapi_update) > Server GC/graz-dc-1b.ad.tao.at/ad.tao.at is not registered with our KDC: Miscellaneous failure (see text): Server (GC/graz-dc-1b.ad.tao.at/ad.tao.at at AD.TAO.AT) unknown > [2017/09/05 10:17:06.015717, 0]

...b/src/gallium/drivers/nouveau/nv30/nv30_draw.c >>> index a681135..03c0c70 100644 >>> --- a/src/gallium/drivers/nouveau/nv30/nv30_draw.c >>> +++ b/src/gallium/drivers/nouveau/nv30/nv30_draw.c >>> @@ -230,22 +230,24 @@ static const struct { >>> [TGSI_SEMANTIC_BCOLOR ] = { EMIT_4F, INTERP_LINEAR , 1, 3, >>> 0x00000004 }, >>> [TGSI_SEMANTIC_FOG ] = { EMIT_4F, INTERP_PERSPECTIVE, 5, 5, >>> 0x00000010 }, >>> [TGSI_SEMANTIC_PSIZE ] = { EMIT_1F_PSIZE, INTERP_POS , 6, 6, >>> 0x00000020 }...

Hi. I have tried to use Package "SEM". As a learning, I try to convert a program running well of EQS which is as follows to SEM: ### EQS ### /SPECIFICATION CAS=100; VAR=5 MAT=COR; ANA=COR; /EQUATIONS V1=*F1+E1; V2=*F1+E2; V3=*F1+*F2+E3; V4=**F1+*F2*E4; V5=*F2+E5; /VAR E1 TO E5=*; F1*1.0; F2=1.0; /COV E1,E2=*; F1,F2=*: /PRINT...

Hello. I am getting results from sem that are not correct (that's assuming that the results from my AMOS 4.0 software are correct). sem does not vary some of the parameters substantially from their starting values, and the final estimates of those parameters as well as the model chisquare value are incorrect. I've attached s...

...m. It seems that the ability to invert the correlation matrix may have something to do with this error, but solve(correl) yields a solution. Here are my correlation matrix and model specifications: --------------------------- R CODE BEGIN ------------------------------------------------ library(sem) correl <- matrix( c(1.0000000,-0.6657822,0.6702089,0.7997673,-0.7225454,0.8992372, -0.8026491,-0.6715168,-0.5781565,-0.6657822,1.0000000,-0.5107568, -0.5030886,0.6971188,-0.6306937,0.7200848,0.5121227,0.4496810, 0.6702089,-0.5107568,1.0000000,0.7276558,-0.3893792,0.6043672, -0.7...

Is it possible to fit a structural equation model with link functions in R? I am trying to build a logistic-regression-like model in sem, because incorporating the dichotomous variables linearly seems inappropriate. Mplus can do something similar by specifying a 'link' parameter, but I would like to be able to do it in R, ofcourse. I have explored the 'sem' package from John Fox, but it does not seem to be able to...

Hello, I finally run my measurement model in sem - successfully. Now, I am trying to print out the path diagram that is based on the results - but for some reason it's not working. Below is my script - but the problem is probably in my very last line: # ANALYSIS OF ANXIETY, DEPRESSION, AND FEAR - LISREL P.31 library(sem) # Creating the ANXIE...