Displaying 20 results from an estimated 10000 matches similar to: "Workshop: structural equation modeling in R"
2005 Dec 04
0
FW: Error in structural equation model - "The model hasnegativedegrees of freedom"
Dear R-help list members,
I forgot to copy my reply to the r-help list. Here's most of it.
John
--------------------------------
John Fox
Department of Sociology
McMaster University
Hamilton, Ontario
Canada L8S 4M4
905-525-9140x23604
http://socserv.mcmaster.ca/jfox
--------------------------------
-----Original Message-----
From: John Fox [mailto:jfox at mcmaster.ca]
Sent: Sunday,
2005 Dec 04
0
Error in structural equation model - "The model has negativedegrees of freedom"
Hi John
Thanks a lot for the reply.
Could you suggest how I can correct this problem? I tried using a
correlation matrix instead of raw moments, but still got the same error. I
also fixed parameters v1,v2,v3,a1 at 1; then it gave me the error that the
system is exatly singular.
To answer the points that you raised:
1. x1-x6 are not causes; they are just indicatiors. Does that change my
2010 Oct 18
0
OpenMX structural equation software
Dear R users,
The OpenMx developer team takes great pride in announcing the availability
of OpenMx 1.0. The team would like to express its gratitude to the large
number of beta-testers who have helped us improve the code. Thank you.
OpenMx is a free suite of R functions and a estimation back-end that
supports fitting a wide variety of structural equation models including
multiple groups, full
2010 Oct 18
0
OpenMX structural equation software
Dear R users,
The OpenMx developer team takes great pride in announcing the availability
of OpenMx 1.0. The team would like to express its gratitude to the large
number of beta-testers who have helped us improve the code. Thank you.
OpenMx is a free suite of R functions and a estimation back-end that
supports fitting a wide variety of structural equation models including
multiple groups, full
2001 Apr 28
9
two new packages
I've prepared preliminary versions of two packages that I plan eventually
to contribute to CRAN:
car (for "Companion to Applied Regression") is a package that provides a
variety of functions in support of linear and generalized linear models,
including regression diagnostics (e.g., studentized residuals, hat-values,
Cook's distances, dfbeta, dfbetas, added-variable plots,
2001 Apr 28
9
two new packages
I've prepared preliminary versions of two packages that I plan eventually
to contribute to CRAN:
car (for "Companion to Applied Regression") is a package that provides a
variety of functions in support of linear and generalized linear models,
including regression diagnostics (e.g., studentized residuals, hat-values,
Cook's distances, dfbeta, dfbetas, added-variable plots,
2001 Apr 28
9
two new packages
I've prepared preliminary versions of two packages that I plan eventually
to contribute to CRAN:
car (for "Companion to Applied Regression") is a package that provides a
variety of functions in support of linear and generalized linear models,
including regression diagnostics (e.g., studentized residuals, hat-values,
Cook's distances, dfbeta, dfbetas, added-variable plots,
2002 Aug 13
1
Ex ante forecasting from structural equation models (SEM package)
Dear Helplist,
I want to produce forecasts from a structural equation model. With the SEM
package the model setup and its estimation is possible. However, I have not
figured out how to obtain ex ante forecasts, i.e. applying the Gauss-Seidel
algorithm to the estimated structural equations for provided values of the
exogenous variables (i.e.: y_t = -inv(A)*B*x_t).
Does anyone know if the there is
2010 Oct 25
1
structural equation modeling in sem, error, The model has negative degrees of freedom = -3, and The model is almost surely misspecified...
Hi all,
I am attempting to learn my way through the sem package by constructing
a simple structural model for some of my data on bird diversity,
abundance, and primary productivity.
I have constructed a covariance matrix between these variables as per
the following:
>S_matrix = matrix(c(
>+ 0.003083259, 0, 0,
>+ 0.143870284, 89.7648490, 0,
>+ 0.276950919,
2004 Nov 23
2
Convergence problem in GLMM
Dear list members,
In re-running with GLMM() from the lme4 package a generalized-linear mixed
model that I had previously fit with glmmPQL() from MASS, I'm getting a
warning of a convergence failure, even when I set the method argument of
GLMM() to "PQL":
> bang.mod.1 <- glmmPQL(contraception ~ as.factor(children) + cage + urban,
+ random=~as.factor(children) + cage +
2011 Aug 13
0
Casualty Actuarial Society request for proposals for R Workshop
I'm a property-casualty actuary, use R in at my job, and lurk on the
list. In conjunction with one of its meetings, the Casualty Actuarial
Society (I'm a member) is looking for proposals from people to teach a
workshop in R and I thought members of the list might be interested.
I've pasted the information below.
My apologies if this posting violates list rules.
Thanks.
Kevin
2011 Nov 07
0
new version 2.0-0 of the sem package
Dear R users,
Jarrett Byrnes and I would like to announce version 2.0-0 of the sem package
for fitting observed- and latent-variable structural equation models. This
is a general reworking of the original sem package (which is still available
on R-Forge as package sem1).
Some highlights of sem 2.0-0 include:
o More convenient and compact model specification, including the default
automatic
2011 Nov 07
0
new version 2.0-0 of the sem package
Dear R users,
Jarrett Byrnes and I would like to announce version 2.0-0 of the sem package
for fitting observed- and latent-variable structural equation models. This
is a general reworking of the original sem package (which is still available
on R-Forge as package sem1).
Some highlights of sem 2.0-0 include:
o More convenient and compact model specification, including the default
automatic
2011 Mar 27
2
Structural equation modeling in R(lavaan,sem)
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 lavaan.
2. I have data that I want to analyse but I have some
2001 Nov 25
2
another optimization question
Dear R list members,
Since today seems to be the day for optimization questions, I have one that
has been puzzling me:
I've been doing some work on sem, my structural-equation modelling package.
The models that the sem function in this package fits are essentially
parametrizations of the multinormal distribution. The function uses optim
and nlm sequentially to maximize a multinormal
2002 Jul 22
2
typsize and fscale arguments to nlm
Dear R list members,
I have a question about the proper use of the typsize and fscale arguments
to nlm.
I use nlm in my sem package to fit general structural-equation models,
which entails maximizing a multinormal likelihood with respect to
parameters that represent regression coefficients and covariances of
variables. The magnitudes of these parameters can be very different.
The
2011 Nov 24
0
sem package (version 2.1-1)
Dear R users,
Version 2.1-1 of the sem package, for structural equation modeling, is now
on CRAN.
Unlike version 2.0-0, which was a major overhaul of the package, version
2.1-1 just sprinkles some syntactic sugar on it, introducing the
specifyEquations() and cfa() functions; specifyEquations() supports model
specification in equation (rather than path) format, and cfa() facilitates
compact
2011 Nov 24
0
sem package (version 2.1-1)
Dear R users,
Version 2.1-1 of the sem package, for structural equation modeling, is now
on CRAN.
Unlike version 2.0-0, which was a major overhaul of the package, version
2.1-1 just sprinkles some syntactic sugar on it, introducing the
specifyEquations() and cfa() functions; specifyEquations() supports model
specification in equation (rather than path) format, and cfa() facilitates
compact
2010 May 19
0
New package: `lavaan' for latent variable analysis (including structural equation modeling)
Dear R-users,
A new package called `lavaan' (for latent variable analysis) has been
uploaded to CRAN. The current version of lavaan (0.3-1) can be used for
path analysis, confirmatory factor analysis, structural equation
modeling, and growth curve modeling.
More information can be found on the website: http://lavaan.org
Some notable features of lavaan:
- the 'lavaan model
2010 May 19
0
New package: `lavaan' for latent variable analysis (including structural equation modeling)
Dear R-users,
A new package called `lavaan' (for latent variable analysis) has been
uploaded to CRAN. The current version of lavaan (0.3-1) can be used for
path analysis, confirmatory factor analysis, structural equation
modeling, and growth curve modeling.
More information can be found on the website: http://lavaan.org
Some notable features of lavaan:
- the 'lavaan model