auto.arima(IR.ts)
Series: IR.ts
ARIMA(1,0,0)(2,1,0)[12]
Coefficients:
ar1 sar1 sar2
0.5896 -0.2163 0.3272
s.e. 0.0972 0.1192 0.1318
sigma^2 = 7.427: log likelihood = -175.04
AIC=358.08 AICc=358.68 BIC=367.19
是系统自动输出的模型,请问我要怎么修改呀