Table 6. Result of gravity model using PPML.

	Coefficient	Contribution	Robust std.err.	z	P>\|z\|
Dist_{i, j}	−0.0005845	−0.06%	0.0001475	−0.32	0.752
GDPcapita_i	−0.0051627	−0.51%	0.0012313	−1.72	0.086
POP_i	2.53E-08	0.00%	3.85E-09	8.64	0.000
GDPcapita_j	0.1162938	12.33%	0.0010273	2.02	0.044
POP_j	−3.12E-07	−0.00%	3.37E-09	−0.05	0.959
Cons	1.99822	-	0.0733776	149.49	0.000

Note) Pseudo log-likelihood: -4,149,270.8, contribution={exp(coefficient)-1}×100