Table 9.

Ranking for best parameters to reduce $R_{df}$.

Region	$R_{df}<1$	$R_{df}\approx 1$
Beijing	$\beta ,\nu ,\left(\mu \right),{\epsilon }_J$	$\beta ,{\epsilon }_J,{\sigma }_2$
Canada	$\beta ,\nu ,\left(\mu \right),{\epsilon }_J$	$\beta ,{\epsilon }_J,{\sigma }_2$
Hong Kong	$\beta ,\nu ,\left(\mu \right),{\epsilon }_J$	$\beta ,{\epsilon }_J,{\sigma }_2$
Singapore	$\beta ,\nu ,\left(\mu \right),{\epsilon }_J$	$\beta ,{\epsilon }_J,{\sigma }_2$