| nodal {DPpackage} | R Documentation |
This data set consider information on the presence of prostatic nodal involvement collected on 53 patients with prostate cancer reported by Brown (1980).
For the sample of prostate cancer patients, a number of possible predictor variables were measured before surgery. The patients then had surgery to determine nodal involvement. It was required to see if nodal involvement could be accurately predicted from the predictor variables and which ones were most important.
data(nodal)
A data frame with 53 observations on the following 7 variables.
idsslnageacidxraysizegradeBrown, B.W. (1980) Prediction analysis for binary data. In Biostatistics Casebook. R.G. Miller, B. Efron, B.W. Brown and L.E. Moses (editors), 3-18. John Wiley.
Chib, S. (1995) Marginal Likelihood from the Gibbs output. Journal of the American Statistical Association, 90: 1313 - 1321.
## Not run:
# Data
data(nodal)
attach(nodal)
lacid<-log(acid)
# Initial state
state <- NULL
# MCMC parameters
nburn<-5000
nsave<-10000
nskip<-10
ndisplay<-100
mcmc <- list(nburn=nburn,nsave=nsave,nskip=nskip,ndisplay=ndisplay,
tune=1.1)
# Prior distribution
prior <- list(alpha=1,beta0=c(0,rep(0.75,5)),
Sbeta0=diag(c(100,rep(25,5)),6))
# Fit the model
fit1 <- DPbinary(ssln~age+lacid+xray+size+grade,prior=prior,mcmc=mcmc,
state=state,status=TRUE)
fit1
## End(Not run)