R OpenBugs Model Error

Question

I am looking to run a hierarchical poisson model to hockey goal tending data. here is the model as set up in bugs:

modelString <- "model {

  for(i in 1:n_obs){

    hockey_goals[i] ~ dpois(p[i])


    log(p[i]) <- p_inter + p_age * age[i] + p_sv_pct * sv_pct[i] + p_team * team[i] + p_win_pct * win_pct[i] + log(n_mins[i])

  }
  p_inter ~ dnorm(0,0.00001)
  p_age ~ dnorm(0, 0.00001)
  p_sv_pct ~ dnorm(0, 0.00001)
  p_team ~ dnorm(0, 0.00001)
  p_win_pct ~ dnorm(0, 0.00001)

}"

I then compile and load the data:

season_goals <- data$GA
n_mins <- data$MIN
age <- data$Age
sv_pct <- data$SV.
team <- data$Tm
win_pct <- data$W/data$GP
data <- list(n_obs=length(season_goals),n_mins=n_mins,hockey_goals=season_goals,age=age,
sv_pct=sv_pct,team=team,win_pct=win_pct)

# Get the data into BUGS:
modelData( bugsData( data ) )
#------------------------------------------------------------------------------
# INTIALIZE THE CHAINS.

nchain = 1
modelCompile( numChains=nchain )
modelGenInits()

#------------------------------------------------------------------------------
# RUN THE CHAINS.
samplesSet( c("p_age","p_sv_pct","p_team","p_win_pct") )
# R command defines a new variable that specifies an arbitrary chain length:
chainLength = 10000
# BRugs tells BUGS to generate a MCMC chain:
modelUpdate( chainLength )

At this point I get an error: Error in handleRes(res) : NA

Any ideas on where I went wrong...?

score 0 · Answer 1 · answered May 09 '17 at 21:03

I wish I could just comment but I don't have enough reputation. Anyway, I made up some data and ran a simplified version of your model (i.e. with only age and minutes played). I ran it in the GUI version of OpenBUGS and it didn't work. I then changed the priors on you coefficients to dnorm(0,0.01) and it updated. So I would suggest changing the priors. The ones you have are very, very vague. Changing them as suggested will not effect your inference and you may get the model to run.

R OpenBugs Model Error

1 Answers1