### Bug fixes

Hey guys: a couple of bug fixes. First of all, there was a mistake in my "outline" of the metropolis code. I had the inequality for the acceptance ratio logic going the wrong direction. The corrected code follows:

```## Sample Metropolis-Hastings algorithm
# function to compute log(h(theta))
log.h <- function(theta,data){

}
met <- function(data,initials,NREP){
# Constants
n <- dim(data)[1]
p <- length(initials)
# Empty matrix to hold samples
chain <- matrix(NA,NREP+1,p)
# Initialize the chain
chain[1,] <- initials
for (i in 2:(NREP+1)){
# Parameters of the proposal
meen <-
var <-
# Draw a proposal value
thetastar <- rnorm(1,meen, var)
# Compute the rejection ratio
logr <- log.h(thetastar) + dnorm(chain[i-1,],meen,sqrt(var),log=T)
- log.h(chain[i-1,]) - dnorm(thetastar,meen,sqrt(var),log=T)
# Decide whether to accept or reject
if (logr > 0){
chain[i,] <- thetastar
} elseif (logr > log(runif(1))) {
chain[i,] <- thetastar
} else {
chain[i,] <- chain[i-1,]
}
}
return(chain[-1,])
}
```

Second, it appears that in the GeoBugs extra credit opportunity, the maps aren't going to load in because it doesn't like negative x values. One solution is to simply add a large constant to all of the longitude values in the polygon file produced by R so that they are positive.