附件是EGARCH的winbugs模型，求帮助！！！
model
{
  # Measurement Equation
  ysigma20 <- 1/(logsigma20)
  
  y0 ~ dnorm(alpha, ysigma20)
  ymean[1] <- alpha + beta * y0
  y[1] ~ dnorm(ymean[1], ysigma2[1])
  for(t in 2:T){
  
    ymean[t] <- alpha + beta * y[t-1]
ysigma2[t] <- 1/(sigma2[t])
    y[t] ~ dnorm(ymean[t], ysigma2[t])
  }
  
  # State Equation
  logsigma20 <- mu
  
  logsigma2[1] <- mu/(1-phi)
  
  sigma[1] <- exp(logsigma2[1]/2)
  
  sigma2[1] <- pow(sigma[1], 2)
  
  ysigma2[1] <- 1/(sigma2[1])
  
  logsigma2[2] <- mu + phi * logsigma2[1] + psi1 * ((y[1]-alpha-beta * y0)/sigma[1]) + psi2 * abs((y[1]-alpha-beta * y0)/sigma[1])
  
  sigma[2] <- exp(logsigma2[2]/2)

  sigma2[2] <- pow(sigma[2], 2)
  for(t in 3:T){
  
    logsigma2[t] <- mu + phi * logsigma2[t-1] + psi1 * ((y[t-1]-alpha-beta * y[t-2])/sigma[t-1]) + psi2 * abs((y[t-1]-alpha-beta * y[t-2])/sigma[t-1])
  
    sigma[t] <- exp(logsigma2[t]/2)

sigma2[t] <- pow(sigma[t], 2)
  
  }
  # Piror Distribution
  alpha ~ dnorm(0, 1)
  beta ~ dnorm(0, 1)
  mu ~ dunif(0, 1)
  phi ~ dunif(0, 1)
  psi1 ~ dunif(0, 1)
  psi2 ~ dunif(0, 1)
}