Table 3. Parameter estimates (mean and 95% credible interval) of selected negative binomial models.
| Parameter | GARIMA(3′,1,0)-SOH-RF | GSARIMA(3′,1,0)×(1,0,0)12 |
| β rain | −0.34 (−0.66, −0.02) | |
| β sin(2πt/12) | −0.10 (−0.23, 0.02) | |
| β cos(2πt/12) | −0.15 (−0.28, −0.02) | |
| β sin(2πt/6) | 0.14 (0.06, 0.21) | |
| β cos(2πt/6) | 0.16 (0.07, 0.24) | |
| φ 3 | −0.10 (−0.19, 0.00) | −0.13 (−0.23, −0.04) |
| φ 1 * | 0.12 (0.03, 0.22) | |
| ψ | 4.54 (3.87, 5.27) | 4.32 (3.69, 5.04) |
| Amplitude AH$ | 0.19 (0.07, 0.32) | |
| Amplitude SAH$ | 0.21 (0.13, 0.29) | |
| Phase shift AH$ | 4.83 (3.30, 6.35) | |
| Phase shift SAH$ | −0.69 (−1.05, −0.34) |
Legend: GARIMA(3′,1,0)-SOH-RF = GARIMA(3,1,0) model with parameters for the first two lags (
and 
) omitted, second order harmonics and rainfall lagged at 2 months (in m); GSARIMA(3′,1,0)×(1,0,0)12 = GSARIMA(3,1,0)×(1,0,0)12 model with parameters for the first two lags (
and 
) fixed to zero; AH = annual harmonic, SAH = semi-annual harmonic; $ = derived parameter, phase shift = phase shift of the cosine function expressed in months.