Displaying 20 results from an estimated 8000 matches similar to: "sem & testing multiple hypotheses with BIC"
2009 Dec 26
5
Is SEM package of R suitable for sem analysis
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
Accounting
2009 Feb 02
1
sem package and AMOS
Hello-
I am using R to build my initial models, but need to use AMOS to compare
the models of two groups (adults vs. kids). The problem is I am getting
different results with R and AMOS for the initial models of the separate
groups (and the R results make more sense).
The parameter estimates (path coefficients and variances) from both
programs are nearly identical, but the model chi-squares
2011 Feb 08
1
SEM: question regarding how standard errors are calculated
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
2006 Mar 16
3
Did I use "step" function correctly? (Is R's step() function reliable?)
Hi all,
I put up an exhaustive model to use R's "step" function:
------------------------
mygam=gam(col1 ~ 1
+ col2 + col3 + col4
+ col2 ^ 2 + col3 ^ 2 + col4 ^ 2
+ col2 ^ 3 + col3 ^ 3 + col4 ^ 3
+ s(col2, 1) + s(col3, 1) + s(col4, 1)
+ s(col2, 2) + s(col3, 2) + s(col4, 2)
+ s(col2, 3) + s(col3, 3) + s(col4, 3)
+ s(col2, 4) + s(col3, 4) + s(col4, 4)
+ s(col2, 5) + s(col3,
2009 May 22
1
Confirmatory factor analysis problems using sem package (works in Amos)
Hello all,
I'm trying to replicate a confirmatory factor analysis done in Amos. The
idea is to compare a one-factor and a two-factor model. I get the following
warning message when I run either model:
"Could not compute QR decomposition of Hessian.
Optimization probably did not converge."
I have no idea what to do here. I believe posters reported the same
problem. It seems
2002 Jul 18
1
sem: incorrect parameter estimates
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 some code that
replicates the problem. The parameters in
2010 Oct 26
3
stripping #s in a text file prior to reading into table or dataframe
I'm importing a lot of text tables of data (from Latent Gold) that includes
hashes in some of the column names ("Cluster#1", "Cluster#2", etc.). Is
there an easy way to strip the offending hashes out before pushing the text
into a table or data frame? I thought I'd use gsub, e.g., but can't figure
out how to read in a text file without reading it into a table or
2007 Mar 07
1
No fit statistics for some models using sem
Hi,
New to both R and SEM, so this may be a very simple question. I am
trying to run a very simple path analysis using the sem package.
There are 2 exogenous (FARSCH, LOCUS10) and 2 endogenous (T_ATTENT,
RMTEST) observed variables in the model. The idea is that T_ATTENT
mediates the effect of FARSCH and LOCUS10 on RMTEST. The RAM
specification I used is
FARSCH -> T_ATTENT, y1x1, NA
2009 Jan 06
1
R SEM package
Does anyone know if the sem package in R can implement a stacked model
comparison, for example as in LISREL or AMOS?
Thanks,
Anthony
--
Anthony Steven Dick, Ph.D.
Post-Doctoral Fellow
Human Neuroscience Laboratory
Department of Neurology
The University of Chicago
5841 S. Maryland Ave. MC-2030
Chicago, IL 60637
Phone: (773)-834-7770
Email: adick at uchicago.edu
Web:
2009 Apr 09
1
CFA in R/sem package
Hi,
I am not sure if R-help is the right forum for my question. If not,
please let me know.
I have to do some discriminant validity tests with some constructs. I
am using the method of doing a CFA constraining the correlation of a
pair of the constructs to 1 and comparing the chi-square of this
constrained model to the unconstrained model. If the chi-square
difference is not significant, then I
2018 Feb 25
3
include
Thank you Jim,
I read the data as you suggested but I could not find K1 in col1.
rbind(preval,mydat) Col1 Col2 col3
1 <NA> <NA> <NA>
2 X1 <NA> <NA>
3 Y1 <NA> <NA>
4 K2 <NA> <NA>
5 W1 <NA> <NA>
6 Z1 K1 K2
7 Z2 <NA> <NA>
8 Z3 X1 <NA>
9 Z4 Y1 W1
On Sat, Feb 24, 2018 at 6:18 PM, Jim
2018 Feb 25
0
include
Hi Val,
My fault - I assumed that the NA would be first in the result produced
by "unique":
mydat <- read.table(textConnection("Col1 Col2 col3
Z1 K1 K2
Z2 NA NA
Z3 X1 NA
Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE)
val23<-unique(unlist(mydat[,c("Col2","col3")]))
napos<-which(is.na(val23))
preval<-data.frame(Col1=val23[-napos],
2013 Jan 11
3
split & rbind (cast) dataframe
Hi,
I would like to split dataframe based on one colum and want
to connect the two dataframes by rows (like rbind). Here a small example:
# The orgininal dataframe
df1 <- data.frame(col1 = c("A","A","B","B"),col2 = c(1:4), col3 = c(1:4))
# The datafame how it could look like
df2 <- data.frame(A.col2 = c(1,2), A.col3 = c(1,2), B.col2 = c(3,4),
B.col3
2018 Feb 25
2
include
Sorry , I hit the send key accidentally here is my complete message.
Thank you Jim and all, I got it.
I have one more question on the original question
What does this "[-1] " do?
preval<-data.frame(Col1=unique(unlist(mydat[,c("Col2","col3")]))[-1],
Col2=NA,col3=NA)
mydat <- read.table(textConnection("Col1 Col2 col3
Z1 K1 K2
Z2
2018 Feb 25
2
include
HI Jim and all,
I want to put one more condition. Include col2 and col3 if they are not
in col1.
Here is the data
mydat <- read.table(textConnection("Col1 Col2 col3
K2 X1 NA
Z1 K1 K2
Z2 NA NA
Z3 X1 NA
Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE)
The desired out put would be
Col1 Col2 col3
1 X1 0 0
2 K1 0 0
3 Y1 0 0
4 W1 0 0
6 K2 X1
2009 Mar 14
2
SEM model testing with identical goodness of fits
HI,
I am testing several models about three latent constructs that
measure risk attitudes.
Two models with different structure obtained identical of fit measures
from chisqure to BIC.
Model1 assumes three factors are correlated with each other and model
two assumes a higher order factor exist and three factors related to
this higher factor instead of to each other.
Model1:
model.one
2010 Oct 11
2
Split rows depending on time frame
Hi,
I have the following data frame, where col2 is a startdate and col3 an
enddate
COL1 COL2 COL3
A 40462 40482
B 40462 40478
The above timeframe of 3 weeks I would like to splits it in weeks like this
COL1 COL2 COL3 COL4
A 40462 40468 1
A 40469 40475 1
A 40476 40482 1
B
2018 Feb 24
3
include
On 24/02/2018 1:53 PM, William Dunlap via R-help wrote:
> x1 = rbind(unique(preval),mydat)
> x2 <- x1[is.na(x1)] <- 0
> x2 # gives 0
>
> Why introduce the 'x2'? x1[...] <- 0 alters x1 in place and I think that
> altered x1 is what you want.
>
> You asked why x2 was zero. The value of the expression
> f(a) <- b
> and assignments
2018 Feb 25
0
include
Jim has been exceedingly patient (and may well continue to be so), but this smells like "failure to launch". At what point will you start showing your (failed) attempts at solving your own problems so we can help you work on your specific weaknesses and become self-sufficient?
--
Sent from my phone. Please excuse my brevity.
On February 25, 2018 7:55:55 AM PST, Val <valkremk at
2018 Feb 25
0
include
hi Val,
Your problem seems to be that the data are read in as a factor. The
simplest way I can think of to get around this is:
mydat <- read.table(textConnection("Col1 Col2 col3
Z1 K1 K2
Z2 NA NA
Z3 X1 NA
Z4 Y1 W1"),header = TRUE,stringsAsFactors=FALSE)
preval<-data.frame(Col1=unique(unlist(mydat[,c("Col2","col3")]))[-1],
Col2=NA,col3=NA)
rbind(preval,mydat)