**WinBugs**** & R**

· What is WinBUGS and how to download it?

· The R project for statistical computing. (you can download R from here)

- Andrew Gelman's Bugs.R webpage Functions for running WinBugs from R. Also, for those of you who have the first edition of the textbook you can download from here the appendix C of the second edition (Example of computation in Bugs and R).

**CODA
& R**

To use **CODA** (Convergence Diagnostic and Output
Analysis) in **R**, you need to have
version 1.09 or later of **R** installed.
Then, click on coda_0.7-1.zip to download the **R-CODA** package, save it, say, in C:\Temp or wherever you prefer. Open **R**, and from the menu bar select Packages, then select Install
package(s) from local zip files, and direct **R**
to the directory where you saved coda_0.7-1.zip, highlight the zip file and
click on Open.

After **R-CODA** is installed you can load it with Load packages or by typing library(coda) at
the R prompt. For help on how to use **R-CODA** type library(help=coda)
at the R prompt.

The following link contains information on how to save WinBugs output to be analyzed by CODA:

The following
link is an article by the original author of **CODA**

Cowles, MK and Carlin, BP
(1995) Markov Chain Monte Carlo diagnostics: A comparative review, *J
Amer Stat Soc*, **91**, 883-904.

**BOA**

You may want to try Bayesian Output Analysis (BOA) instead of CODA. It is based on CODA but it handles better machine resources. You can download either the S-plus or R version from here: http://www.public-health.uiowa.edu/boa/

**FROM
R TO WinBugs**

writeDatafileR.txt is a function for outputting data from R to WinBUGS written by Terry Elrod. You have to save it to disk, say, to C:\Temp, and then read it into R with the command:

source("C:/Temp/writeDatafileR.txt").

To use it, type in the R command prompt

writeDatafileR(x,file1)

where x is either a data.frame or else a list (which
contains no lists), and file1 is the name of the file where you want the data
in WinBugs format be stored.

For example the code

x=c(15,26,10,9,15,20,18,11,8,20,7,9,10,11,11,10,12,42,17,11,10)

y=c(95,71,83,91,102,87,93,100,104,94,113,96,83,84,102,100,105,57,121,86,100)

CPO = 1:21

z=data.frame(cbind(x,y,CPO))

writeDatafileR(z,"D:/gabe/forWB.txt")

will create a file in D:/gabe/ called forWB.txt that
will contain this:

list( x = c( 15, 26, 10, 9, 15, 20, 18, 11, 8, 20, 7, 9, 10, 11, 11, 10, 12,

42, 17, 11, 10) , y = c( 95, 71, 83, 91, 102, 87, 93, 100, 104, 94, 113, 96,

83, 84, 102, 100, 105, 57, 121, 86, 100) , CPO = c( 1, 2, 3, 4, 5, 6, 7, 8, 9,

10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21) )

Then you can copy and paste the above into your WinBugs
code.

If you use S-plus instead of R you can download from here the same function written for S-plus: