Principles of Modern Psychological Measurement: A Festschrift for Frederic M. Lord
Author: Howard Wainer
Edition: 1 (1983) Publisher: Lawrence Erlbaum Associates hardcover: 416 pages
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Tuesday, July 13, 2010
books Want to Buy
Monday, April 12, 2010
JAGS
Working on simulation for a paper, I use JAGS fro cross-verification.
1. http://www-fis.iarc.fr/~martyn/software/jags/ get 1.03 package for windows
it seems that 1.04 has been released but not available for windows yet.
http://calvin.iarc.fr/wordpress/
2. http://www-fis.iarc.fr/~martyn/software/jags/ for installation and example
a short intro with an example www.stat.ufl.edu/~rsteorts/jags_present.pdf
Saturday, April 10, 2010
logistic regression and classification/PS
Walker and Duncan (1967) longitudinal logistic classification model.
1. data collected in a 10-year period
2. number of variables is huge
The observations are not independent to one another;
model selection and variable reduction;
Cornfield ( 1962) argued that "The use of a mathematical model which summarizes the observations in a small number of disposable parameters seems to offer the only present hope of obtaining quantitative answers to questions of interest".
If the parameters are disposable, how would we know it is replicable and reliable? And how much the results (classification results) based on the disposable parameters are reliable?
Is this, related to or set up the theoretical tone for, sample-based classification modeling (internal classification)? 



Monday, June 01, 2009
wget in Ubuntu
Archived some classical materials of a master's course
Create a dir first then cd thisfolder then run the following in terminal.
greenlinux4r@greenlinux4r-desktop:~/Desktop/DavidThissenPSY840$ sudo wget -r -l 2 -np http://www.unc.edu/courses/2007spring/psyc/840/001/
Wednesday, May 27, 2009
R on the cluster
Running Bayesian models on Ubuntu using WinBUGS in R. A downside of it is that WinBUGS window will not close automatically. Running the same bugs code using loop works in windows system. Dr. Gleman suggested to use OpenBUGS on Linux system through version=2 option. It allows the code run on back stage. But insalling OpenBUGS on linux is a little bit painful. Before jumping to OpenBUGS, I first tried to run some bugs jobs on HPCC cluster.
loading modu R:
@brody:~> module unload mvapich
@brody:~> module load openmpi
@brody:~> module load R
@brody:~> R
~> library(Rmpi)
# to get a code editor so you can try some code. This is not a good idea. Try code on local #computer may be preferable.
> install.packages(Rcmdr)
I failed to call it on the cluster. I may let it go and find another route.
Now I am going to try JAGA. http://www-fis.iarc.fr/~martyn/software/jags/
It has been suggested to be used in linux. http://www.nabble.com/Re:-R-vs.-Bugs-p18060894.html
Saturday, May 16, 2009
Combine biased and unbiased samples
It appears on Statistical Science V21 N.4 2006 Nov. p517
biased sample: non-random sample/ convenient sample
Graves et al (2006) developed a hypergeometric model with a bias parameter to identify the feature-prevalence in a population when convenient samples are used. MCMC was used and the prior on bias parameter was set as lognormal.
Graves et al (2006) was on Technometrics.
Wednesday, January 14, 2009
Rmpi on a multiple-cpu pc under linux system
RMPI: An R package that can execute message passing interface, which allows parellel computaion in R enviroment.
On an multiple cpu computer such as Dell insprion 530, on can run RMPI for parellel compution. Suppose Rmpi has been
installed completely in R following the instruction (rmpi README file).
Open a Terminal, type
greenlinux4r@greenlinux4r-desktop:~$ lamclean
greenlinux4r@greenlinux4r-desktop:~$ lamboot -v
LAM 7.1.2/MPI 2 C++/ROMIO - Indiana University
n-1<6366> ssi:boot:base:linear: booting n0 (localhost)
n-1<6366> ssi:boot:base:linear: finished
greenlinux4r@greenlinux4r-desktop:~$ mpiexec -n 4 R --no-save -q
master (rank 0, comm 1) of size 4 is running on: greenlinux4r-desktop
slave1 (rank 1, comm 1) of size 4 is running on: greenlinux4r-desktop
slave2 (rank 2, comm 1) of size 4 is running on: greenlinux4r-desktop
slave3 (rank 3, comm 1) of size 4 is running on: greenlinux4r-desktop
One master and three co-working CPUs have been activated for use.
Now, run R code to let the co-working CPUS to identify themselves.
mpi.remote.exec(paste("I am",mpi.comm.rank(),"of",mpi.comm.size()))
$slave1
[1] "I am 1 of 4"
$slave2
[1] "I am 2 of 4"
$slave3
[1] "I am 3 of 4"
All co-working CPUS can be closed and Rmpi can be exited using
> mpi.close.Rslaves()
[1] 1
> mpi.quit([saving=yes/no])
type in yes to save workplace, otherwise no.
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