各位高手:

我在用如下的语句:

roll.fit=roll(FUN=garch,data=hp.s,width=24,incr=3,formula.mean=~1,formula.var~garch(1,1))

出现错误:

Problem in timeDate(start): First (charvec) argument to function time must be of type character
Use traceback() to see the call stack


请教大家到底哪里出了问题???


谢谢了