Table 4. Implementation of the residual heterogeneity test, 1991–2020, Taiwan.

Breusch Pagan Godfrey test	Model 1	Model 2	Model 3
F-statistic	0.162832 (0.6896)	0.09177 (0.7642)	0.212240 (0.6486)
OBS* R-squared	0.173454 (0.6771)	0.098004 (0.7542)	0.225689 (0.6347)
Scaled explained SS	0.464775 (04954)	0.076161 (0.7826)	0.991503 (0.3194)

*The regression equations of model 1, model 2 and model 3 are derived from Table 4