Table 2.

Descriptive statistical analysis.

Model	Variable		Sample size	Mean	Standard deviation	Max.	Min.
A: Sample affected by the ASF epidemic
Armington model	The relative demand for imports	Y it	605	−5.86	1.62	−3.04	−12.16
	Relative price	X it	605	0.43	0.46	2.80	−2.07
	Lags a period relative prices	X it−1	594	0.42	0.46	2.80	−2.07
Breakpoint regression model 1	The growth rate of pork imports	increase i	592	0.32	3.65	84.00	−0.94
Threshold regression model	Impact of ASF	ASF t	611	−0.94	5.69	1.48	1
Breakpoint regression model 2	Chinese price of pork	$\text{ln }{P}_i^M$	611	1.15	0.51	1.96	0.49
	Chinese Pork Imports from Country i	ln Mi	611	15.65	1.57	18.31	9.39
	The import price of pork	$\text{ln }{P}_i^D$	611	0.73	0.44	3.98	−0.88
	The exchange rate	ln ratei	611	1.68	2.12	7.06	0.03
B: Sub–samples suffering from the impact of COVID−19
Armington model	The relative demand for imports	Y it	364	−5.52	1.51	−3.04	−10.81
	Relative price	X it	364	0.61	0.49	2.80	−2.07
	Lags a period relative prices	X it−1	364	0.58	0.49	2.80	−2.07
Threshold regression model	Impact of COVID−19	COVID t	143	2022.865	2922.703	13610.37	6.81
Breakpoint regression model 2	Chinese price of pork	$\text{ln }{P}_i^M$	364	1.44	0.48	1.96	0.66
	Chinese Pork Imports from Country i	ln Mi	364	15.93	1.46	18.31	10.8
	The import price of pork	$\text{ln }{P}_i^D$	364	0.83	0.52	3.98	−0.88
	The exchange rate	ln ratei	364	1.65	2.11	6.97	0.03