	(1)	(2)	(3)
	a1	a2	a3
VARIABLES	VAS1	修正VAS	客户上游度
			
DDD	-0.0977786***	0.0373691**	0.0914736*
	(-4.037)	(2.228)	(1.745)
Size	-0.1320903***		0.0174114
	(-8.317)		(0.318)
Lev	-0.0321757		0.2827895**
	(-0.560)		(2.202)
ROA	-0.2362354**		0.1407633
	(-2.042)		(0.530)
FirmAge	0.0576716		0.4699415
	(0.772)		(1.407)
FIXED	0.1684243**		0.3246884*
	(2.463)		(1.705)
INV	-1.4759859***		-0.3784667*
	(-10.302)		(-1.727)
Board	0.0509716		0.1743675
	(0.884)		(0.916)
Indep	0.0002750		0.0063963
	(0.177)		(0.971)
Dual	0.0071120		-0.0139226
	(0.401)		(-0.277)
TOP1	-0.0009548		-0.0014695
	(-1.095)		(-0.504)
Big4	-0.0202128		0.0813210
	(-0.427)		(0.500)
size_chain		-0.0147395***	
		(-3.164)	
age_chain		-0.0192085	
		(-1.300)	
roa_chain		0.0240226	
		(0.744)	
lev_chain		-0.0748504***	
		(-3.738)	
固定资产比资产		-0.0478380	
		(-1.134)	
存货比资产		-0.1094169***	
		(-3.529)	
Constant	3.2414813***	0.9307572***	-1.5775217
	(8.103)	(13.515)	(-0.912)
			
Observations	6,538	7,901	4,238
R-squared	0.501	0.541	0.483
企业层面控制变量	YES	YES	YES
年份固定效应	YES	YES	YES
个体固定效应	YES	YES	YES
Robust t-statistics in parentheses			
*** p<0.01, ** p<0.05, * p<0.1			
