Displaying 20 results from an estimated 1000 matches similar to: "sampling weights for multilevel models"
2010 Mar 25
1
A file with extension .sdb in a codebook section of a large database from a survey?
The TIMSS2007 database http://timss.bc.edu/TIMSS2007/idb_ug.html seems
to provide "both kinds" of universal data formats - either SPSS saved
data sets or SAS saved data sets. (Yes, I am being sarcastic.)
These, of course, are accompanied by massive codebooks explaining the
nature of each of the fields in the data sets. The T07_Codebooks.zip
file available at that site contains .pdf
2005 Nov 27
2
multilevel models and sample size
It is not a pure R question,but I hope some one can give me advices.
I want to use analysis my data with the multilevel model.The data has 2 levels---- the second level has 52 units and each second level unit has 19-23 units.I think the sample size is quite small,but just now I can't make the sample size much bigger.So I want to ask if I use the multilevel model to analysis the data set,will
2012 Apr 30
3
R2 in multilevel modelling
Goodmorning everybody,
i'm an italian statistician and i'm using R for research.
Could someone tell me some indices to see the goodness of fit in multilevel
modelling?
I'm using the lmer function, and I want to know if my model fit well my
data.
I actually want to justify the use of multilevel model instead the classical
one.
Hope someone can help me.
Thank you.
Greetings
2003 Apr 08
3
Multilevel Analyses in R
I am new to R and would like to get some practice analyzing multilevel data. I wonder if anyone can point me to a sample data set and command lines that I might replicate for a sample session. I would then compare my output with HLM output.
Any help is appreciated.
------
Harold C. Doran
Director of Research and Evaluation
New American Schools
675 N. Washington Street, Suite 220
Alexandria,
2003 Aug 25
2
Book recommendations: Multilevel & longitudinal analysis
Hi, does anyone out there have a recommendation for multilevel / random
effects and longitudinal analysis?
My dream book would be something that's both accessible to a
non-statistician but rigorous (because I seem to be slowly turning into a
statistician) and ideally would use R.
Peter
2006 Mar 01
1
Book: Multilevel Modeling in R ETA?
Hi R folks (Dr. Bates in particular),
In August 2005, Dr. Bates mentioned that the documentation for lme4
"will be in the form of a book with the working title 'Multilevel
Modeling in R'" and I'm just wondering if there is an estimated date of
publication or if it's still a long way off. The Rnews article does a
great job of introducing the package, but I'm
2006 Oct 02
1
multilevel factor model in lmer
Hello --
I am curious if lmer can be used to fit a multilevel factor model such as a
two-parameter item response model. The one parameter model is
straightforward. A two-factor model requires a set of factor loadings
multiplying a single random effect. For example, a logit model for the ith
subject responding correctly to the jth item (j=1,..,J) is
logit[p(ij)] = a1*item1(i) + ... + aJ *
2007 Apr 16
1
Modelling Heteroscedastic Multilevel Models
Dear ListeRs,
I am trying to fit a heteroscedastic multilevel model using lmer{lme4-
package). Take, for instance, the (fictive) model below.
lmer(test.result ~ homework + Sex -1 + (1 | School))
Suppose that I suspect the error terms in the predicted values to
differ between men and women (so, on the first level). In order to
model this, I want the 'Sex'-variable to be random on
2007 Jan 18
2
Help with problem - multilevel model?
I have what is probably a very simple problem but I would be very
grateful to the list for any help or pointers to implement a solution in
R.
We have two types of measurements on the eye that we have collected in
62 patients at 5 fixed time points during a clinical visit over an
office day. We want to establish if there is an association between the
measurements. Obviously it would be wrong to
2011 Sep 07
1
Reshaping data from wide to tall format for multilevel modeling
Hi,
I'm trying to reshape my data set from wide to tall format for multilevel
modeling. Unfortunately, the function I typically use (make.univ from the
multilevel package) does not appear to work with unbalanced data frames,
which is what I'm dealing with.
Below is an example of the columns of a data frame similar to what I'm
working with:
ID a1 a2 a4 b2 b3 b4 b5 b6
Below
2010 Jul 22
2
Multilevel survival model
* Please cc me if you reply as I am a digest subscriber *
Hi,
I am wondering how I can run a multilevel survival model in R? Below is
some of my data.
> head(bi0.test)
childid famid lifedxm sex age delta
1 22.02 22 CONTROL MALES 21.36893 0
2 13.02 13 MAJOR MALES 21.18001 0
3 64.02 64 CONTROL MALES 20.09377 0
4 5.02 5 CONTROL FEMALES
2008 Jun 15
2
R vs SAS and HLM on multilevel analysis- basic question
Hi R users!
I am trying to learn some multilevel analysis, but unfortunately i am now very confused. The reason: http://www.ats.ucla.edu/stat/hlm/seminars/hlm_mlm/mlm_hlm_seminar.htm
http://www.ats.ucla.edu/stat/sas/seminars/sas_mlm/mlm_sas_seminar.htm
and
MlmSoftRev. pdf from mlmRev package.
>From what i see, the first two links seem to declare the level one variable as a random part (i
2009 Mar 17
2
Multilevel modeling using R
Dear All,
I use R to conduct multilevel modeling. However, I have a problem about the interpretation of random effect. Unlike the variables in fixed effects, the variables in random effects have not shown the p-value, so I don't know whether they are significant or not? I want to obtain this figure to make the decision. Thanks a lot!
Below is the syntax and output of my program:
2010 Mar 14
2
code rows depending on the value of other rows in multilevel dataframe
I have a multilevel dataframe (df):
ID Date Segment Slice Tract Lesion
1 CSPP005 12/4/2007 1 1 LCST 0
2 CSPP005 12/4/2007 1 1 LPC 2
3 CSPP005 12/4/2007 1 1 RPC 3
4 CSPP005 12/4/2007 1 1 RCST 1
5 CSPP005 12/4/2007 1 1 LGM 0
6 CSPP005 12/4/2007 1 1
2013 May 14
1
Sampling Weights and lmer() update?
Perhaps I am not looking in the right place, but I am looking for a way to
use lmer() to run a multilevel model that incorporates sampling weights. I
have used the Lumley survey package to use sampling weights in the past,
but according to post I found online from Thomas Lumley in mid-2012, R is
currently not equipped to be able to do this.
His post is here:
2010 Mar 06
2
Plot interaction in multilevel model
I am trying to plot an interaction in a multilevel model. Here is some
sample data. In the following example, it is longitudinal (i.e., repeated
measures), so the outcome, score (at each of the three time points), is
nested within the individual. I am interested in the interaction between
gender and happiness predicting score.
id <- c(1,1,1,2,2,2,3,3,3)
age <-
2005 Jun 09
2
can nlme do the complex multilevel model?
data from multilevel units,first sample the class ,and then the student in calss.following is the 2-level model. and the level-1 model deals with the student,and the level-2 model deals with the class level the students belong to.
Level-1 Model
Y = B0 + B1*(ZLEAD) + B2*(ZBUL) + B3*(ZSHY) + R
Level-2 Model
B0 = G00 + U0
B1 = G10 + G11*(ZWARMT) + U1
B2 = G20 + G21*(ZWARMT) + G22*(ZABLET) +
2006 Oct 22
1
Multilevel model ("lme") question
Dear list,
I'm trying to fit a multilevel (mixed-effects) model using the lme function
(package nlme) in R 2.4.0. As a mixed-effects newbie I'm neither sure about
the modeling nor the correct R syntax.
My data is structured as follows: For each subject, a quantity Y is measured
at a number (>= 2) of time points. Moreover, at time point 0 ("baseline"), a
quantity X is
2006 Nov 07
3
question on multilevel modeling
Hi,
I am trying to run a multilevel model with time nested in people and
people nested in dyads (3 levels of nesting) by initially running a
series of models to test whether the slope/intercept should be fixed or
random. The problem that I am experiencing appears to arise between the
random intercept, fixed slope equation AND.
(syntax:
rint<-lme(BDIAFTER~BDI+WEEK+CORUMTO,
2010 Mar 26
1
Multilevel modeling with count variables
I am using a multilevel modeling approach to model change in a person's
symptom score over time (i.e., longitudinal individual growth models). I
have been using the lme function in the multilevel package for the analyses,
but my problem is that my outcome (symptoms) and one of my predictors
(events) are count data, and are non-normal. Do you have any suggestions
for how to deal with them?