在论坛里下的代码如下
model
{
for (i in 1:n) {
Ymean[i]<-rho/tau*exp(0.5*theta[i])*(theta[i+1]-mu-phi*(theta[i]-mu));
Yisigma2[i] <- 1/(exp(theta[i])*(1-rho*rho));
y[i]~ dnorm(Ymean[i],Yisigma2[i]);
}
isigma2<-(1-phi*phi)*itau2; ***这里为什么要出现这个呢?
theta0 ~ dnorm(mu,isigma2);
thetamean[1] <- mu + phi*(theta0-mu);
theta[1] ~ dnorm(thetamean[1],itau2);
for (i in 2:(n+1)) {
thetamean[i] <- mu + phi*(theta[i-1]-mu);
theta[i]~dnorm(thetamean[i],itau2);}
phi1 ~ dbeta(20,1.5);
phi <- 2*phi1-1;
mu ~ dnorm(0,0.04);
itau2 ~ dgamma(2.5,0.025);
tau <- sqrt(1/itau2) ;
rho ~ dunif(-1,1)
}
update时出现cannot sample from slice for node itau2???是怎么回事,而且运行反应特别慢
还是为什么要出来isigma2这个呢