Table 2.

Estimate parameters of the ARIMA models for STDs.

STDs	Variable	Estimate	Standard error	t	P-value	AIC	SBC
One-year prediction
AIDS						−0.533	−0.383
	AR(2)	−0.721	0.159	−4.539	<0.001
	AR(1)	−0.231	0.106	−2.175	0.032
	MA(2)	0.763	0.206	3.710	<0.001
	SMA(1)	−0.677	0.095	−7.111	<0.001
	Constant	0.003	0.006	−0.449	0.655
Gonorrhea					−1.376	−1.251
	AR(1)	−0.421	0.065	−6.506	<0.001
	MA(2)	−0.516	0.127	−4.050	<0.001
	SMA(2)	0.273	0.118	2.306	0.023
	Constant	0.001	0.006	0.233	0.816
Syphilis						0.207	0.331
	AR(3)	0.279	0.138	2.017	0.046
	MA(2)	−0.985	0.119	−8.279	<0.001
	SAR(1)	−0.916	0.070	−13.081	<0.001
	SMA(2)	0.314	0.128	2.465	0.015
Five−year prediction
AIDS						−0.311	−0.010
	AR(2)	−0.689	0.191	−3.602	0.001
	AR(1)	−0.388	0.173	−2.244	0.029
	MA(1)	−0.646	0.163	−3.959	<0.001
	SMA(2)	0.639	0.306	2.088	0.042
	Constant	−0.001	0.009	−0.124	0.902
Gonorrhea					−2.089	−1.984
	AR(3)	0.472	0.102	4.620	<0.001
	AR(2)	0.380	0.092	4.117	<0.001
Syphilis						−2.052	−1.876
	AR(2)	−0.454	0.140	−3.249	0.002
	AR(1)	−0.834	0.105	−7.949	<0.001
	MA(1)	−0.626	0.140	−4.490	<0.001
	Constant	−0.002	0.002	−0.775	0.442

SAR, seasonal AR lags; SMA, seasonal MA lags.