Research Article

The Level of Regional Economic Development, Green Image, and Enterprise Environmental Protection Investment: Empirical Evidence from China

Table 5

Robustness test.

VariablesUse marketization index to measure regional economic development levelAdd control variables to the model
NEIMarketNEIEIMarketEI

GIM0.279 (3.25)0.571 (8.33)0.245 (2.81)0.317 (3.55)0.584 (8.12)0.285 (3.15)
Market0.061 (2.46)0.054 (2.11)
EPS−0.161 (−0.98)0.040 (0.30)−0.163 (−1.00)−0.802 (−3.61)−0.269 (−1.45)−0.788 (−3.54)
LEV−0.001 (−0.41)−0.010 (−4.47)−0.001 (−0.19)−0.001 (−0.45)−0.009 (−3.59)−0.001 (−0.29)
FLOW0.552 (1.05)0.161 (0.38)0.542 (1.03)−0.104 (−0.18)0.048 (0.10)−0.107 (−0.18)
CASH0.147 (0.44)0.831 (3.38)0.096 (0.29)−0.070 (−0.20)0.673 (2.63)−0.107 (−0.31)
Tobin−0.009 (−0.21)−0.120 (−4.06)−0.001 (−0.03)0.022 (0.44)−0.123 (−3.32)0.028 (0.58)
SIZE0.870 (23.29)−0.218 (−7.09)0.884 (23.47)0.930 (20.37)−0.237 (−6.20)0.942 (20.56)
AGE−0.064 (−6.53)0.012 (1.64)−0.065 (−6.62)−0.061 (−5.66)0.012 (1.46)−0.062 (−5.72)
COST−0.002 (−0.21)0.006 (0.68)−0.003 (−0.24)
SHARE−0.106 (−1.41)0.063 (1.06)−0.109 (−1.46)
ROE0.018 (3.84)0.011 (2.82)0.018 (3.72)
YEARControlControlControlControlControlControl
Constant−2.455 (−3.14)13.001 (20.04)−3.246 (−3.87)−3.609 (−3.70)13.056 (15.97)−4.312 (−4.23)
N2,7282,7282,7282,6162,6162,616
R20.2180.1900.2202,5212,5212,521
Adj_R20.2130.1850.2150.2210.1870.223
F53.6042.9250.550.2150.1810.217
F(-value)0.00000.00000.00000.00000.00000.0000

Notes. , , and represent the significance level of 1%, 5%, and 10% respectively; t value is in parentheses, and results are subject to standard error handling.