Displaying 20 results from an estimated 1000 matches similar to: "sem with categorical data"
2010 Jan 03
1
Questions regarding sem using hetcor() function from polycor and diagrams
Hello R Users,
While I have attempted to dig into the R help files and I have not
identified the answer to these questions, I apologize in advance if my
questions were answered in the past. I also recognize that one of my
questions unfortunately verges on statistical rather than code
territory. I have two rather unrelated questions about using the sem and
polycor packages for a relatively
2011 Feb 14
4
sem problem - did not converge
Someone can help me? I tried several things and always don't converge
# Model
library(sem)
dados40.cov <- cov(dados40,method="spearman")
model.dados40 <- specify.model()
F1 -> Item11, lam11, NA
F1 -> Item31, lam31, NA
F1 -> Item36, lam36, NA
F1 -> Item54, lam54, NA
F1 -> Item63, lam63, NA
F1 -> Item65, lam55, NA
F1 -> Item67, lam67, NA
F1 ->
2013 Jan 23
2
CFA with lavaan or with SEM
Hi
Sorry for the rather long message.
I am trying to use the cfa command in the lavaan package to run a CFA however I am unsure over a couple of issues.
I have @25 dichotomous variables, 300 observations and an EFA on a training dataset suggests a 3 factor model.
After defining the model I use the command
fit.dat <- cfa(model.1, data=my.dat, std.lv = T, estimator="WLSMV",
2009 Feb 02
1
Fit indexes in SEM with categorical data + ML estimation
Hello,
It has been found that SEM analysis using polychoric correlations + maximum
likelihood estimator produces incorrect test statistics and standard errors
(e.g., Flora, D. B., & Curran, P. J. (2004). An Empirical Evaluation of
Alternative Methods of Estimation for Con?rmatory Factor Analysis With
Ordinal Data. Psychological Methods, 9(4), 466-491).
Standard errors can be dealt with by
2007 Aug 12
1
SEM for categorical data
Hi
I am looking for a structural equation modeling package in R which can be
used for categorical data. Is anyone aware of the existence of such a
package? Would appreciate any help on this.
Thank you
Upasna
--
---------------------------------------------------------------------
Upasna Sharma
Research Scholar
Shailesh J. Mehta School of Management,
Indian Institute of Technology, Bombay
2012 Nov 16
1
polycor package
I am currently working with R's polycor package and I have encountered a
problem. I tried to follow the steps as outlined in the sem.pdf file where
a CFA model is run using polychoric correlations. Every time I run the
command sem(model, data, N=.), I get the following warning message:
Warning message:
In if (orthogonal) { :
the condition has length > 1 and only the first element will be
2013 Feb 01
2
Nested loop and output help
Hello Everyone,
My name is Thomas and I have been using R for one week. I recently found
your site and have been able to search the archives of posts. This has
given me some great information that has allowed me to craft an initial
design to an inquiry I would like to make into the breakdown of McNemar's
test. I have read an intro to R manual and the posting guides and hope I am
not violating
2011 Oct 11
1
warning with cut2 function
Dear r user,
please find my attached sample of the dataset i? am using to create a crosstable and eventually plot a histogram from the output.
I am using? the cut2 function to create bins, about 7 of them using the code after reading the data:
cluster <- cut2(cross_val$value, g=7)
I get the warning:
Warning message:
In min(xx[xx > upper]) : no non-missing arguments to min; returning Inf
2006 Dec 01
3
error in hetcor function (polycor package)?
I have been using the hetcor function in the polycor package. When I
don't specify the use option everything runs smoothly. However, when I
specify use either as "pairwise.complete.obs" or "complete.obs" I get
this error
Error in optim(rho, f, control = control, hessian = TRUE, method =
"BFGS") :
non-finite value supplied by optim
Is this an error in
2004 Jul 06
3
Improving effeciency - better table()?
Hi,
I've been running some simulations for a while and the performance of R
has been great. However, I've recently changed the code to perform a sort
of chi-square goodness-of-fit test. To get the observed values for each
cell I've been using table() - specifically I've been using cut2 from
Hmisc to divide up the range into a specified number of cells and then
using
2012 Oct 17
2
cut2 error
To R users,
I am trying to use cut2 function from the 'Hmisc' library. However, when I
try and run the function on the following variable, I get an error message
(displayed below). I suspect it is because of the NA but I have no idea
how to address the error. Many thanks to any insights.
structure(list(var1 = c(97, 97, 98, 98, 97, 99, 97,
98, 99, 98, 99, 98, 98, 97, 97, 98, 99, 98,
2012 Oct 17
2
loop of quartile groups
Greetings R users,
My goal is to generate quartile groups of each variable in my data set. I
would like each experiment to have its designated group added as a
subsequent column. I can accomplish this individually with the following
code:
brks <- with(data_variables,
cut2(var2, g=4))
#I don't want the actual numbers, I need a numbered group
data$test1=factor(brks,
2009 Oct 23
1
cut2 once, bin twice...
Hello,
I'm using the Hmisc cut2 function to bin a set of data. It produces bins
that I like with results like this:
[96,270]:171
[69, 96): 54
[49, 69): 40
[35, 49): 28
[28, 35): 14
[24, 28): 8
(Other) : 48
I would like to take a second set of data, and assign it to bins based on
factors defined by my call to cut 2.
Does anyone know how I can do this?
Thank you,
-S
--
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2008 May 29
1
appropriate covariance matrix for multiple nominal exogenous and multiple continuous endogenous variables in SEM
Hi,
I would like to use the sem package to perform a path analysis (no
latent variables) with a mixture of 2 nominal exogenous, 1 continuous
exogenous, and 4 continuous endogenous variables. I seek advice as to
how to calculate the appropriate covariance matrix for use with the sem
package.
I have read through the polycor package, and am confused as to the use
of "numeric" for
2010 Mar 08
1
Help with Hmisc, cut2, split and quantile
Hello,
I have a set of data with two columns: "Target" and "Actual". A
http://n4.nabble.com/file/n1584647/Sample_table.txt Sample_table.txt is
attached but the data looks like this:
Actual Target
-0.125 0.016124906
0.135 0.120799865
... ...
... ...
I want to be able to break the data into tables based on quantiles in the
"Target" column. I can see (using
2007 Apr 15
1
Fit sem model with intercept
Hi - I am trying to fit sem model with intercepts. Here is what I have in my model.
Exogeneous vars: x1 (continous), x2 (ordinal), x3 (ordinal), x4(continuous)
Endogeneous vars: y1 (continuous), y2 (ordinal), y3 (ordinal)
SEM model:
x1 -> eta1; x2 -> eta1; x3 -> eta2; x4 -> eta2; eta1 -> y1, eta1 -> y2, eta2 -> y2, eta2 -> y3
However, in these arrow models, I
2011 Mar 08
1
SEM error
Dear All,
I am new for R and SEM. I try to fit the model with Y (ordinal outcome), X
(4 categorical data), M1-M3 (continuous), and 2 covariates (Age&sex) as a
diagram.
library(polycor)
model.ly <-specify.model()
1: x -> m1, gam11, NA
2: x -> m2, gam12, NA
3: x -> m3, gam13, NA
4: age -> m1, gam14, NA
5: age -> m2, gam15, NA
6: age -> m3, gam16, NA
7: sex -> m1,
2005 Oct 10
1
SEM with dichotomous indicators
Hello,
I'd like to know if there is a way to fit a Structural equation model with
dichotomous indicators (ex: problem with a phone solved/ or not) having
effects on a ordinal variable.
How I do that using R?
Do you have an example with the code in R that you can send to me?
Thanks a lot!
Renata Estrella
UFRJ, Brasil, Rio de Janeiro
Renata Leite Estrella
Assistente de
2005 Jan 07
3
lognorm
Hi!
I 've a problem to have a lognorm distribution with
mean=1 and var (or sigma)=1.
rlnorm(1000,0,0)
rlnorm(1000,1,1)
rlnorm(1000,0,1)
.... ?
Can you help me?
2008 May 04
1
Is my understanding of rlnorm correct?
rlnorm takes two 'shaping' parameters: meanlog and sdlog.
meanlog would appear from the documentation to be the log of the mean.
eg if the desired mean is 1 then meanlog=0.
So to generate random values that fit a lognormal distribution I would
do this:
rlnorm(N , meanlog = log(mean) , sdlog = log(sd))
But when I check the mean I don't get it when sdlog>0. Interestingly I