Code for Drivers example
#Load the data set
data(Drivers)
#Define the formula
formula = sqrt(y) ~ belt + f(trend,model="rw2",param=c(1,0.0005)) +
f(seasonal,model="seasonal",season.length=12,param=c(1,0.1))
#lounch the inla function
mod = inla(formula, family="gaussian", data=Drivers,
control.family=list(param=c(4,4)))