r - garchFit 错误：solve.default(fit$hessian) 中的错误：系统在计算上是奇异的：倒数条件数 = 9.58802e-18

Question

我正在使用 R 来拟合 AR-GARCH 模型并得到以下错误。有没有办法解决它？

fit1=garchFit(~ arma(1,0)+garch(2,1), data = M1[,1], cond.dist = "sstd", trace = FALSE)
Error in solve.default(fit$hessian) : 
  system is computationally singular: reciprocal condition number = 9.58802e-18