Displaying 20 results from an estimated 400 matches similar to: "Book recommendations: Multilevel & longitudinal analysis"
1999 Aug 31
1
basic help
Sorry to ask this but does anyone knows a good text that helps with the
basic programming side of R. I understand the statistics behind most
of R but i have real difficulty with the data types and how R views
them.
As a part of that could you help me with another problem. I know how
to read data in from a file in terms of read.table but how do i single
a column out or even just download a
1999 Apr 15
2
regression with uncertainty in both variables
Hi, all.
I'm trying to use some linear regression models in which both the
dependent and independent variables are measured with some error. To
make things worse, while the errors in the dependent variable are uniform,
the errors in the independent (or explanatory, or "x") variables can be
heteroskedastic. I've been looking at the book _Measurement Error Models_
by Fuller
2001 Dec 09
1
plot.design()
Greetings-
I'm working through Pinheiro and Bates' _Mixed Effects Models in S and
S-Plus_ using R (1.3.1 for linux). On page 13 (okay, so I haven't got that
far :)) is:
plot.design( ergoStool)
which returns on my system:
> plot.design(ergoStool)
Error: couldn't find function "plot.design"
any ideas?
Thanks.
2003 Oct 04
2
(no subject)
Dear all,
I have the following question. I have to fit the hierarchical model for the
hypothesis concern the individual-level effects by controlling for the
individual -level attributes and national-level contextual effects on
individuals by using R.
O have to obtain the estimates of the impact of the second-level (national:
GDP per capita) effects on individuals ( in this instance the impact
2003 Jul 24
4
Problem w/ source
I'm trying to use the source command to run commands from a file. For
instance: source("do.R"), where do.R is a file in the same directory in
which I am running R.
The contents of do.R are:
ls()
print("hello")
sum(y1)
mean(y1)
After source("do.R"), all I see is:
> source("do.R")
[1] "hello"
I'm using the X11 version of R for
2018 Apr 13
0
Longitudinal and Multilevel Data in R and Stan: 5-day workshop May 28 to June 1, 2018
Longitudinal and Multilevel Data in R and Stan
ICPSR short course: May 28 to June 1, 2018
May 28: Introduction to R by John Fox
May 29 to June 1: Longitudinal and Multilevel Data in R and Stan by Georges Monette
Sponsored and organized by ICPSR, University of Michigan and
held at York University in Toronto, Ontario
Course description:https://www.icpsr.umich.edu/icpsrweb/sumprog/courses/0226
2003 Jul 14
2
Hypothesis testing after optim
Hi folks: Does anyone know of a way to do (linear) hypothesis tests of
parameters after fitting a maximum-likelihood model w/ optim? I can't seem
to find anything like a Wald test whose documentation says it applies to
optim output.
Also, thanks again to everyone who gave me feedback on the robustness of ML
estimation in R!
Peter
********************************
2003 Jul 13
3
How robust is mle in R?
A newbie question: I'm trying to decide whether to run a maximum likelihood
estimation in R or Stata and am wondering if the R mle routine is reasonably
robust. I'm fairly certain that, with this data, in Stata I would get a lot
of complaints about non-concave functions and unproductive steps attempted,
but would eventually have a successful ML estimate. I believe that, with
the
2002 Aug 12
1
Select exactly n elements of a vector
In discussing permutation tests, _Modern Applied Statistics With S Plus_ suggests this (IMHO) rather elegant approach to generating a distribution of t-tests:
d<- ...some data...
ttest <- function(x) mean(x)/sqrt(var(x)/length(x))
n<-1000
res<-numeric(n)
for(i in 1:n) res[i] <- ttest(x<-d*sign(runif(10)-0.5)
The problem is that the sign(runif) results in random permutation of
2005 Jan 18
2
Function to modify existing data.frame
I'm used to statistical languages, such as Stata, in which it's trivial to
pass a list of variables to a function & have that function modify those
variables in the existing dataset rather than create copies of the variables
or having to replace the entire dataset to change a few variables. In R, I
suppose I could paste together the right instructions in a function and then
execute
2012 Jan 13
2
cannot find -lquadmath
Apologies if this has been posted about recently, but I haven't been
on this listserve for a while.
I ran into a problem trying to compile Hmisc (required package for
rms) and have found a solution that I'd like to share. The compile
fails with the message:
/usr/bin/ld: cannot find -lquadmath
libquadmath exists on my Debian Squeeze system (up-to-date, recently installed):
ldconfig -p
2010 Feb 05
3
metafor package: effect sizes are not fully independent
In a classical meta analysis model y_i = X_i * beta_i + e_i, data
{y_i} are assumed to be independent effect sizes. However, I'm
encountering the following two scenarios:
(1) Each source has multiple effect sizes, thus {y_i} are not fully
independent with each other.
(2) Each source has multiple effect sizes, each of the effect size
from a source can be categorized as one of a factor levels
2003 Jun 21
2
Beginner's Question on Linear Regression Models
Hi Folks,
Could anyone point me to a good reference on linear regression models? Specifically, I am trying to gain an intuitive feel for how the standard error values are calculated for the parameter estimates. My understanding is that these are computed using the variance-covariance matrix computed from the input data matrix. Although I think I understand the math, I still don't have a
2010 Feb 23
1
Longitudinal analysis: contrasting time points
Hi everyone
I have the following situation:
In a longitudinal study, subjects fill out a questionnaire every year
(repeated measurements over time). Also, the subjects are nested within
departments. There is an intervention going on over time. The outcome
variable is continuous. Now I'd like to analyse two things:
1. Is there a significant change over time? I think this is done by a
2005 Dec 22
2
Testing a linear hypothesis after maximum likelihood
I'd like to be able to test linear hypotheses after setting up and running a
model using optim or perhaps nlm. One hypothesis I need to test are that
the average of several coefficients is less than zero, so I don't believe I
can use the likelihood ratio test.
I can't seem to find a provision anywhere for testing linear combinations of
coefficients after max. likelihood.
Cheers
2006 Jan 05
2
Wald tests and Huberized variances (was: A comment about R:)
On Wed, 4 Jan 2006, Peter Muhlberger wrote:
One comment in advance: please use a more meaningful subject. I would have
missed this mail if a colleague hadn't pointed me to it.
> I'm someone who from time to time comes to R to do applied stats for social
> science research.
[snip]
> I would also prefer not to have to work through a
> couple books on R or S+ to learn how to
2003 Jun 25
2
within group variance of the coeficients in LME
Dear listers,
I can't find the variance or se of the coefficients in a multilevel model
using lme.
I want to calculate a Chi square test statistics for the variability of the
coefficients across levels. I have a simple 2-level problem, where I want to
check weather a certain covariate varies across level 2 units. Pinheiro
Bates suggest just looking at the intervals or doing a rather
2002 May 02
2
problem with lme in nlme package
Dear R list members,
I've turned up a strange discrepancy between results obtained from the lme
function in the nlme package in R and results obtained with lme in S-PLUS.
I'm using version 3.1-24 of nlme in R 1.4.1 under Windows 2000, and both
S-PLUS 2000 and 6.0, again under Windows 2000.
I've noticed discrepancies in a couple of instances. Here's one, using data
from Bryk
2004 Aug 27
4
FIML in lme
Hi
I was asked if lme can use FIML (Full Information Maximum Likelihood)
instead of REML or ML but I don't know the answer. Does anybody know if
this is implemented in R?
Thanks
Francisco
2003 Jul 25
1
Programs stopped working--.print (newbie question)
I must have messed up my R environment, but don't know how or how to undo
it. The problem is this:
I paste the following into R:
test<-function()
{
print("hello")
}
And I see this:
> test<-function()
+ {
+ .print("hello")
+ }
> test()
Error in test() : couldn't find function ".print"
>
When I do the same in a fresh environment, I see