Descriptive statistics
Table 2 shows the descriptive statistical results of the main variables. The mean value of listed companies’ R&D investment (CRD) is 4.111 and the standard deviation is 1.451, indicating that there is a large gap in the R&D investment status among different listed companies. The mean value of air quality (AQI) is 2.983, the median is 2.994 and the standard deviation is 0.708, indicating that the air quality in cities of China has been evenly distributed in recent years and in some areas it has been improved. The mean value of investor sentiment is -0.007 and the standard deviation is 0.342, the maximum stock return is 13.197 and the minimum is -0.044, indicating that the impact of investor sentiment on the returns of various enterprises is very different. The mean value of government supervision is 51.068 and the standard deviation is 246.852, indicating that the government’s support is obvious but there is great heterogeneity. The statistical results of other variables are in line with overall situation of enterprises in China. Therefore, it is very necessary to analyze the heterogeneity of the research in this paper. From the statistical results, we can see that non-key pollution monitoring companies, non-state-owned companies, non-pollution companies accounted for a large proportion of the sample.
Table 2
Descriptive statistical analysis of variables
Variable
|
N
|
Mean value
|
Standard deviation
|
Minimum
|
Median
|
Maximum
|
Continuous variable
|
|
lnCRD
|
11787
|
4.111
|
1.451
|
-8.722
|
4.071
|
9.993
|
AQI
|
11787
|
2.983
|
0.708
|
0.003
|
2.994
|
5.378
|
Sent
|
11787
|
-0.007
|
0.342
|
-1.055
|
-0.044
|
13.197
|
Sent0
|
11787
|
-0.006
|
0.346
|
-1.055
|
-0.044
|
13.197
|
ALE
|
11787
|
0.336
|
0.234
|
0
|
0.31
|
8.009
|
TCD
|
11787
|
-0.971
|
2.565
|
-6.604
|
-0.489
|
6.792
|
TCD0
|
11787
|
0.409
|
2.291
|
-4.807
|
0.634
|
4.561
|
CYP
|
11787
|
7.191
|
4.663
|
0.296
|
6.436
|
34.036
|
GDP
|
11787
|
0.085
|
0.057
|
-0.374
|
0.087
|
0.615
|
GS
|
11787
|
51.068
|
246.852
|
-4.796
|
11.531
|
11267.000
|
Size
|
11787
|
9.522
|
0.508
|
7.765
|
9.463
|
12.282
|
Cash
|
11787
|
0.125
|
0.113
|
0
|
0.092
|
0.887
|
FCF
|
11787
|
0.054
|
0.108
|
-1.686
|
0.048
|
2.005
|
CYP
|
11787
|
7.185
|
4.657
|
0.296
|
6.436
|
34.036
|
Virtual variable
|
11787
|
|
Value=1
|
Value=0
|
Control
|
11787
|
0.5
|
Frequency=2625
|
Frequency=9162
|
State
|
11787
|
0.5
|
Frequency=542
|
Frequency=11245
|
Pollute
|
11787
|
0.5
|
Frequency=1685
|
Frequency=10102
|
Benchmark regression analysis
Table 3 shows the benchmark regression results of formula (1), the models (1) and (2) are the regression results of fixed effect and random effect with the listed companies’ R&D investment as the explained variable, and the models (3) and (4) are the regression results of fixed effect and random effect with the listed companies’ R&D personnel as the explained variable.
Table 3
Benchmark regression results
Variable name
|
lnCRD
|
lnCRP
|
Fixed effect(1)
|
Random effect(2)
|
Fixed effect(3)
|
Random effect(4)
|
AQI
|
-0.2097***
|
-0.1894***
|
-0.0388*
|
-0.0498***
|
|
(-6.9603)
|
(-8.0856)
|
(-1.6695)
|
(-2.5913)
|
ALE
|
0.0859
|
0.0299
|
-0.0368
|
-0.0628
|
|
(0.9769)
|
(0.3633)
|
(-0.8256)
|
(-1.4555)
|
CYP
|
0.0104
|
0.0165***
|
0.0117
|
0.0114***
|
|
(0.6911)
|
(3.2147)
|
(1.1741)
|
(2.7188)
|
GDP
|
-0.0320
|
0.0703
|
-0.0547
|
-0.0008
|
|
(-0.3022)
|
(0.6790)
|
(-0.6736)
|
(-0.0102)
|
Size
|
1.7822***
|
1.6914***
|
1.3783***
|
1.3307***
|
|
(21.6285)
|
(31.4112)
|
(21.6825)
|
(29.1435)
|
Cash
|
-0.5255***
|
-0.4267***
|
-0.4269***
|
-0.3681***
|
|
(-7.0324)
|
(-5.9688)
|
(-5.5348)
|
(-4.9537)
|
FCF
|
0.3788***
|
0.4195***
|
0.2001***
|
0.2198***
|
|
(4.4937)
|
(4.9398)
|
(2.8784)
|
(3.1568)
|
TCD
|
-0.0085***
|
-0.0114***
|
0.0002
|
-0.0011
|
|
(-3.1615)
|
(-4.3038)
|
(0.1531)
|
(-0.7476)
|
Cons
|
-12.2772***
|
-11.5754***
|
-7.5244***
|
-7.0937***
|
|
(-15.1026)
|
(-22.6254)
|
(-12.0061)
|
(-16.1485)
|
Observ
|
11,782
|
11,782
|
11,782
|
11,782
|
R-squared
|
0.2565
|
|
0.2483
|
|
*** p<0.01, ** p<0.05, * p<0.1, value t in brackets, the following is the same |
According to the regression results of model (1)-(4), the estimated coefficients of AQI are all negative at the significant level of 1%, and the economic implications are as follows: Taking model (1) as an example, the regression coefficient of -0.2097 indicates that an increase of 1 unit in the Air Quality Index (AQI) reduces the R&D investment of listed companies by 20.97% of the total asset investment at the beginning of the period. It shows that the worse the air quality is, the less the R&D investment of the listed companies is.
Table 4
Benchmark regression of intermediary effect of investor sentiment
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
lnCRD
|
Sent
|
lnCRD
|
lnCRP
|
Sent
|
lnCRP
|
Sent
|
|
|
-0.0662***
|
|
|
-0.0158*
|
|
|
|
(-4.8844)
|
|
|
(-2.5093)
|
AQI
|
-0.2097***
|
0.0684***
|
-0.2052***
|
-0.0388*
|
0.0684***
|
-0.0377*
|
|
(-6.9603)
|
(4.4385)
|
(-6.8075)
|
(-1.6695)
|
(4.4385)
|
(-2.6213)
|
ALE
|
0.0859
|
-0.0694***
|
0.0813
|
-0.0368
|
-0.0694***
|
-0.0379
|
|
(0.9769)
|
(-3.1939)
|
(0.9296)
|
(-0.8256)
|
(-3.1939)
|
(-0.8509)
|
CYP
|
0.0104
|
0.0022
|
0.0106
|
0.0117
|
0.0022
|
0.0118
|
|
(0.6911)
|
(0.4557)
|
(0.7011)
|
(1.1741)
|
(0.4557)
|
(1.1776)
|
GDP
|
-0.0320
|
-0.0223
|
-0.0335
|
-0.0547
|
-0.0223
|
-0.0550
|
|
(-0.3022)
|
(-0.3762)
|
(-0.3167)
|
(-0.6736)
|
(-0.3762)
|
(-0.6782)
|
Size
|
1.7822***
|
-0.3062***
|
1.7619***
|
1.3783***
|
-0.3062***
|
1.3735***
|
|
(21.6285)
|
(-7.8641)
|
(21.2364)
|
(21.6825)
|
(-7.8641)
|
(21.5553)
|
Cash
|
-0.5255***
|
0.4169***
|
-0.4979***
|
-0.4269***
|
0.4169***
|
-0.4203***
|
|
(-7.0324)
|
(7.4550)
|
(-6.6443)
|
(-5.5348)
|
(7.4550)
|
(-5.4334)
|
FCF
|
0.3788***
|
0.1226***
|
0.3870***
|
0.2001***
|
0.1226***
|
0.2020***
|
|
(4.4937)
|
(3.2590)
|
(4.5650)
|
(2.8784)
|
(3.2590)
|
(2.9016)
|
TCD
|
0.0085***
|
0.0077***
|
0.0080***
|
0.0002
|
0.0077***
|
0.0003
|
|
(3.1615)
|
(4.8100)
|
(2.9906)
|
(0.1531)
|
(4.8100)
|
(0.2380)
|
Cons
|
-12.2772***
|
2.6592***
|
-12.1010***
|
-7.5244***
|
2.6592***
|
-7.4824***
|
|
(-15.1026)
|
(6.8395)
|
(-14.8004)
|
(-12.0061)
|
(6.8395)
|
(-11.9124)
|
Observ
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
R-squar
|
0.2565
|
0.0395
|
0.2582
|
0.2483
|
0.0395
|
0.2485
|
Table 4 shows the intermediary effect benchmark regression results of formula (2), and the intermediary variable is investor sentiment (Sent). In Table 4, the models (1)-(3) are the regression results of the intermediary effect with the listed companies’ R&D investment as the explained variable, and the models (4)-(6) are the regression results of the intermediary effect with the listed companies’ R&D personnel as the explained variable. The results show that the explanatory variable air quality (AQI) has a significantly positive influence coefficient b1 on the intermediary variable investor sentiment (Sent) whether for R&D investment or for R&D personnel. It means that air pollution can stimulate investor sentiment. At this time, the explanatory variable air quality (AQI) and the intermediary variable investor sentiment (Sent) in columns 3 and 6 have significant coefficients c1 and c2 for the explained variable R&D investment, and b1c2 and c1 have the same sign, indicating that investor sentiment has a intermediary effect between air quality and R&D investment. The former regression coefficient for investor sentiment is -0.0662, and for air quality (AQI) it is -0.2052, both of which are significant at the 1% significance level. The latter regression coefficient for investor sentiment is -0.0158, and for air quality it is -0.0377, both of which are significant at the 10% significance level. And the regression coefficient of air quality on investor sentiment is 0.0684, which is significant at the 1% significance level. The results of the models (1)-(3) are consistent with those of the models (4)-(6). In general, air quality has a significant inhibitory effect on R&D Investment, and the inhibitory effect is slightly weakened when the intermediary variables are added. And because air quality has a significant effect on investor sentiment, this approach further restrains the R&D investment of listed companies. On the whole, with the aggravation of air pollution, the R&D investment of enterprises will decrease under the capital crowding-out effect and human resource loss effect. Especially, the high-tech talents with stronger ability to avoid pollution and better ability to bear population flow will lead to the decline of innovation quality of enterprises in polluted areas.
From a micro perspective, the higher the degree of air pollution is, the higher the investor sentiment is. And different from the previous research conclusion, it has an indirect inhibitory effect on the R&D investment of listed companies by using investor sentiment as the influence path. And the indirect effect of this part is -0.0045. This indicates that the upsurge of investment sentiment caused by the increase of air pollution level has not stimulated the innovation vigor of the listed companies, but may hinder the financing constraints of enterprises and weaken the sensitivity of the R&D investment of the listed companies, and at the same time, the rationality of managers and the irrationality of investors have a reverse effect, which does not cater to investors and indirectly restrains the R&D Investment of listed companies.
Table 5
Benchmark regression of intermediary effect of government supervision
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
lnCRD
|
GS
|
lnCRD
|
lnCRP
|
GS
|
lnCRP
|
GS
|
|
|
0.0001***
|
|
|
0.0001*
|
|
|
|
(3.7468)
|
|
|
(1.7671)
|
AQI
|
-0.2097***
|
17.4213***
|
-0.2107***
|
-0.0388*
|
17.4213***
|
-0.0399*
|
|
(-6.9603)
|
(2.8326)
|
(-7.0893)
|
(-1.6695)
|
(2.8326)
|
(-1.7204)
|
ALE
|
0.0859
|
0.5735
|
0.0858
|
-0.0368
|
0.5735
|
-0.0368
|
|
(0.9769)
|
(0.0885)
|
(0.9779)
|
(-0.8256)
|
(0.0885)
|
(-0.8284)
|
CYP
|
0.0104
|
2.4878**
|
0.0103
|
0.0117
|
2.4878**
|
0.0116
|
|
(0.6911)
|
(2.3313)
|
(0.6814)
|
(1.1741)
|
(2.3313)
|
(1.1576)
|
GDP
|
-0.0320
|
-1.9886
|
-0.0319
|
-0.0547
|
-1.9886
|
-0.0546
|
|
(-0.3022)
|
(-0.0845)
|
(-0.3014)
|
(-0.6736)
|
(-0.0845)
|
(-0.6723)
|
Size
|
1.7822***
|
69.9067***
|
1.7782***
|
1.3783***
|
69.9067***
|
1.3739***
|
|
(21.6285)
|
(4.8003)
|
(21.7415)
|
(21.6825)
|
(4.8003)
|
(21.7172)
|
Cash
|
-0.5255***
|
-7.9296
|
-0.5251***
|
-0.4269***
|
-7.9296
|
-0.4264***
|
|
(-7.0324)
|
(-0.5836)
|
(-7.0309)
|
(-5.5348)
|
(-0.5836)
|
(-5.5321)
|
FCF
|
0.3788***
|
19.3797
|
0.3777***
|
0.2001***
|
19.3797
|
0.1988***
|
|
(4.4937)
|
(1.5523)
|
(4.4826)
|
(2.8784)
|
(1.5523)
|
(2.8651)
|
TCD
|
0.0085***
|
2.6200***
|
0.0087***
|
0.0002
|
2.6200***
|
0.0001
|
|
(3.1615)
|
(5.1923)
|
(3.1998)
|
(0.1531)
|
(5.1923)
|
(0.0381)
|
Cons
|
-12.2772***
|
-683.3977***
|
-12.2382***
|
-7.5244***
|
-683.3977***
|
-7.4811***
|
|
(-15.1026)
|
(-4.6944)
|
(-15.1983)
|
(-12.0061)
|
(-4.6944)
|
(-11.9962)
|
Observ
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
R-squar
|
0.2565
|
0.0076
|
0.2567
|
0.2483
|
0.0076
|
0.2488
|
Table 5 shows the intermediary effect benchmark regression results of formula (2), and the intermediary variable is government supervision (GS). In Table 5, the models (1)-(3) are the regression results of the intermediary effect with the listed companies’ R&D investment as the explained variable, and the models (4)-(6) are the regression results of the intermediary effect with the listed companies’ R&D personnel as the explained variable. The results show that the explanatory variable air quality (AQI) has a significantly positive influence coefficient b1 on the intermediary variable government supervision (GS) whether for R&D investment or for R&D personnel. It means that air pollution will be of effective concern to the government and measures will be taken in response. At this time, the explanatory variable air quality (AQI) and the intermediary variable government supervision (GS) in columns 4 and 6 have significant coefficients c1 and c2 for the explainatory variable R&D investment, and b1c2 and c1 have the same sign, indicating that government supervision has a masking effect between air quality and R&D investment. The former regression coefficient for government supervision is 0.0001, and for air quality (AQI) it is -0.2052, both of which are significant at the 1% significance level. The latter regression coefficient for government supervision is 0.0001, and for air quality it is -0.0399, both of which are significant at the 10% significance level. And the regression coefficient of air quality on investor sentiment is 17.4213, which is significant at the 1% significance level. The results of the models (1)-(3) are consistent with those of the models (4)-(6).
The aggravation of air pollution can indeed attract the effective attention of the government and cause the government to implement the corresponding subsidy policies. The implementation of corresponding subsidy policies can also indirectly increase R&D investment of listed companies. But at the same time, it may cause enterprise managers to pay too much attention to this kind of speculative profit-seeking and expand the demand for their own interests. Enterprises may be less motivated to innovate, which in turn reduces investment in research and development The crowding-out effect of government supervision may offset or even outweigh its promotional effect.
Since the results of the explained variables in Tables 4 and 5 are consistent, the empirical results of R&D investment represented by R&D fund investment and R&D personnel are robust, and the results of R&D fund investment are more significant, therefore, the later empirical analysis of this paper only uses R&D fund investment as the explained variable.
Further discussion-Heterogeneity of listed companies
Air quality, technical complexity and R&D investment of listed companies
Among the results in Tables 4 and 5, it is noteworthy that the urban technical complexity (TCD) is an indicator closely related to enterprise R&D innovation,and in Tables 4 and 5, the regression results of technological complexity on enterprise R&D innovation are both significant at the 1% level. Technical complexity represents the comparative advantage of urban technology. At present, enterprise innovation is based on the innovation of complex products, not the innovation of single technology, so it needs the support of multi-technology. Therefore, the technological complexity of the cities where the listed companies are located determines the differences in the environments in which they conduct their innovation activities. This paper classifies the technical complexity by means of average value. The cities above the average value are high technical complexity areas, marked as 1, on the contrary low technical complexity areas, marked as 0. It is a region with low technical complexity and is recorded as 0. The empirical results are shown in Tables 6 and 7.
Table 6
Heterogeneity analysis of technical complexity based on investor sentiment
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
TCD=1
|
TCD=0
|
lnCRD
|
Sent
|
lnCRD
|
lnCRD
|
Sent
|
lnCRD
|
Sent
|
|
|
-0.0839***
|
|
|
-0.0331
|
|
|
|
(-4.2125)
|
|
|
(-1.1818)
|
AQI
|
-0.1883***
|
0.0744***
|
-0.1820***
|
-0.2422***
|
0.1137***
|
-0.2385***
|
|
(-4.6909)
|
(3.9158)
|
(-4.5532)
|
(-4.9624)
|
(4.4195)
|
(-4.8363)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-14.7636***
|
2.4895***
|
-14.5549***
|
-10.6680***
|
2.9073***
|
-10.5717***
|
|
(-13.6394)
|
(4.8420)
|
(-13.3668)
|
(-9.3950)
|
(4.1917)
|
(-9.3053)
|
Observ
|
7,033
|
7,033
|
7,033
|
4,749
|
4,749
|
4,749
|
R-squar
|
0.2688
|
0.0375
|
0.2710
|
0.3305
|
0.0520
|
0.3310
|
Table 6 presents the grouped regression results of high-tech and low-tech complexity regions, with investor sentiment as the intermediary variable, where the models (1)-(3) are samples of high-tech complexity regions and the models (4)-(6) are samples of low-tech complexity regions. In the models (1)-(3), the influence coefficient b1 of explanatory variable air quality (AQI) on investor sentiment (Sent) of intermediary variable was significantly positive. It means that air pollution can stir up investor sentiment. At this point, the explanatory variable air quality (AQI) and the intermediary variable investor sentiment (Sent) in column 3 are both significant for coefficients c1, c2 for the explained variable R&D investment, and b1c2 and c1 are the same number, indicating that investor sentiment still has an intermediary effect between air quality and R&D investment. However, in the models (4)-(6), the influence coefficient b1 of the explanatory variable air quality (AQI) on the investor sentiment (Sent) of the intermediary variable is significantly positive, but there is no longer an intermediary effect, indicating that investor sentiment, as the impact path of air quality and R&D investment of listed companies, needs the technical complexity of the region to reach a certain degree, and comparing model (1) and model (4), air quality has stronger inhibition on R&D Investment of listed companies in low-tech complex areas. As cities become more technologically diverse, on the one hand, enterprises are more likely to have access to complementary technology support, providing a good environment and external support to undertake complex innovation activities. On the other hand, technological diversity can also enhance the possibility of technology integration, which is conducive to the formation of emerging industries, enhance the managers' expectation of future earnings and the competitiveness of the industry, and thus can effectively encourage enterprises to increase R&D investment.
Table 7 shows the group regression results for high-tech complexity regions and low-tech complexity regions with government concerns as the intermediary variables, with the same model setting as Table 6. The coefficients c1 and c2 of the explanatory variable air quality (AQI) and the intermediary variable government concern (GS) in column 3 are significant, and the b1c2 and c1 are different, indicating that the government is concerned about the masking effect between air quality and R&D investment. However, in the models (4)-(6), the influence coefficient b1 of the explanatory variable air quality (AQI) on investor sentiment (Sent) of the intermediary variable is significantly positive, but c1 is not significant, so in low-tech complex areas, government concern cannot be the impact path of air pollution and R&D investment of listed companies. Comparing model (2) and model (5), the influence coefficient of air quality on government concern in high-tech complexity areas is 1.8849, and in low-tech complexity areas it is 37.5347. Both are significant at 1% level, but the difference is large. The coefficient in Table 5 is 17.4213, indicating that at present, the government is more sensitive to air pollution and more urgent to promote the improvement of regional innovation ability in the regions with low technological complexity. In this state, the government subsidy does not play a crowding-out role.
Table7 Heterogeneity analysis of technical complexity based on government Concern
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
TCD=1
|
TCD=0
|
lnCRD
|
GS
|
lnCRD
|
lnCRD
|
GS
|
lnCRD
|
GS
|
|
|
0.0003*
|
|
|
-0.0000
|
|
|
|
(1.7118)
|
|
|
(-0.1896)
|
AQI
|
-0.1883***
|
1.8849***
|
-0.1888***
|
-0.2422***
|
37.5347***
|
-0.2417***
|
|
(-4.6909)
|
(4.3996)
|
(-4.7330)
|
(-4.9624)
|
(3.5305)
|
(-5.0878)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-14.7636***
|
-604.9122***
|
-14.5774***
|
-10.6680***
|
-671.2972***
|
-10.6777***
|
|
(-13.6394)
|
(-3.2341)
|
(-13.7161)
|
(-9.3950)
|
(-4.5849)
|
(-9.4735)
|
Observ
|
7,033
|
7,033
|
7,033
|
4,749
|
4,749
|
4,749
|
R-squar
|
0.2688
|
0.0151
|
0.2706
|
0.3305
|
0.0051
|
0.3305
|
Air quality, property rights and R&D investment of listed companies
According to the nature of the actual controller, this paper defines the property right nature of listed companies (State) as the virtual variable. State takes 1 if it belongs to a state-owned enterprise, and 0 if it belongs to a non-state-owned enterprise. Table 8 is a grouped regression result of the property rights nature with investor sentiment as the intermediary variable, in which the model (1)-(3) is the sample of state-owned enterprises, and the model (4)-(6) is the sample of non-state-owned enterprises. The estimation coefficient of AQI on investor sentiment in models (1) - (3) is not significant, while the estimated coefficient of AQI in models (4) - (6) is significantly positive at the level of 1%. The above results show that air pollution has an intermediary effect on R&D investment of non-state-owned enterprises, while no on the R&D investment of state-owned enterprises.
Enterprises with different property rights are confronted with different political environments. Non-state-owned enterprises face more stringent regulatory pressure than state-owned enterprises. At the same time, non-state-owned enterprises are likely to bear more environmental responsibility from the government, and investor sentiment in non-state-owned polluting enterprises is notably higher when air pollution levels rise, in this case, the investors will have a "pessimistic expectation" to the expected return and effectiveness, leading to the reduction of their R&D investment.
Table 8
Heterogeneity analysis of enterprise based on investor sentiment
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
State=1
|
State=0
|
lnCRD
|
Sent
|
lnCRD
|
lnCRD
|
Sent
|
lnCRD
|
Sent
|
|
|
-0.0803
|
|
|
-0.0679***
|
|
|
|
(-0.5662)
|
|
|
(-5.0177)
|
AQI
|
-0.5334**
|
0.0505
|
-0.5294**
|
-0.2016***
|
0.0798***
|
-0.1962***
|
|
(-2.1505)
|
(0.9744)
|
(-2.0988)
|
(-6.9542)
|
(5.1653)
|
(-6.7861)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-12.0816***
|
1.3064
|
-11.9767***
|
-12.3722***
|
2.7287***
|
-12.1868***
|
|
(-3.5386)
|
(1.1531)
|
(-3.5818)
|
(-14.9896)
|
(6.8262)
|
(-14.6594)
|
Observ
|
542
|
542
|
542
|
11,240
|
11,240
|
11,240
|
R-squar
|
0.1556
|
0.0177
|
0.1563
|
0.2685
|
0.0376
|
0.2704
|
Table 9 is a grouped regression result with the property right nature as the intermediary variables, in which the model (1)-(3) is the sample of state-owned enterprises, and the model (4)-(6) is the sample of non-state-owned enterprises. In column 3,the coefficient c2 of the intermediary variable government concern to the explained variable R&D investment is not significant, which indicates that there is no intermediary effect in the sample of state-owned enterprises, and the air quality is not significant to the government concern. However, in the models (4)-(6), the coefficient b1 of the impact of explanatory variable air quality on the investor sentiment of the intermediary variable is significantly positive, and the b1c2 and c1 are showing opposite signs༌which indicates that there is a masking effect between the government concern on air quality and R&D investment.
In order to improve the economic performance, local governments will intervene in market competition by means of administrative monopoly to protect the state-owned holding companies. Local governments pay more attention to protecting the interests of state-owned enterprises and give more policy support to state-owned enterprises that are at a disadvantage in the market competition. As a result, government concern is not on its own a path of influence for air pollution and R&D investment by listed companies, and it is not sensitive to air pollution for state owned enterprises. As air pollution intensifies, state-owned polluters are protected even as the government sets more binding environmental policies, and their R&D investment is not significantly affected by air pollution. For the non-state-owned enterprises, government concern as a significant intermediary variable, its crowding-out effect on R&D investment still exists.
Table9 Heterogeneity analysis of enterprises based on the government concern
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
State=1
|
State=0
|
lnCRD
|
GS
|
lnCRD
|
lnCRD
|
GS
|
lnCRD
|
GS
|
|
|
-0.0000
|
|
|
0.0001***
|
|
|
|
(-0.5510)
|
|
|
(4.1397)
|
AQI
|
-0.5334**
|
22.5496
|
-0.5327**
|
-0.2016***
|
21.0234***
|
-0.2039***
|
|
(-2.1505)
|
(0.8900)
|
(-2.1569)
|
(-6.9542)
|
(3.0925)
|
(-7.0757)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-12.0816***
|
-650.4609
|
-12.1015***
|
-12.3722***
|
-670.8661***
|
-12.2982***
|
|
(-3.5386)
|
(-1.0173)
|
(-3.5668)
|
(-14.9896)
|
(-4.5015)
|
(-15.0412)
|
Observ
|
542
|
542
|
542
|
11,240
|
11,240
|
11,240
|
R-squar
|
0.1556
|
0.0016
|
0.1559
|
0.2685
|
0.0095
|
0.2689
|
Air quality, polluting enterprises and R&D investment of listed companies
The intermediary effect of "air quality-enterprise R&D investment" may be affected by the characteristics of the pollution degree of the enterprise itself. This article takes the "Notice on the Implementation of Special Emission Limits for Air Pollutants" issued by the Ministry of Environmental Protection as the standard. If the listed company is in the six major industries under the “Notice”, it will be defined as a heavy pollution enterprise, and the rest will be defined as light pollution enterprises. In this article, the pollution degree of an enterprise (Pollute) is defined as a virtual variable. If it is a heavily polluting enterprise, the Pollute value is 1; if it is a lightly polluting enterprise, the Pollute value is 0.
Table 10 presents the grouped regression results of heavy and light polluting enterprises with investor sentiment as the intermediary variable, in which the models (1)-(3) are the samples of heavy polluting enterprises, and (4)-(6) are the samples of light polluting enterprises. Both of them have a significant intermediary effect, and there is no significant difference between the two groups in the regression results of the intermediary variable of investor sentiment. However, in terms of the overall effect, compared with light polluters, heavy polluters' R&D investment is more restrained by air quality. The above results show that air pollution has a more obvious impact on R&D investment of heavily polluting enterprises. Heavy polluting enterprises generally belong to high energy-consuming industries, and most of them are local pillar industries. They should bear more responsibility for environmental protection, but they are prone to the phenomenon of ‘collusion between government and enterprises’, which makes such enterprises pay less attention to environmental protection and do not implement the principle of ‘polluter pays’.
Table 11 presents the grouped regression results of heavy and light polluting enterprises with government concern as the intermediary variable, in which the models (1)-(3) are the samples of heavy pollutng enterprises, and (4)-(6) are the samples of light polluting enterprises.There is significant intermediary effect in the sample of heavy polluting enterprises, while there is no intermediary effect in the sample of light polluting enterprises. Comparing model (2) and (5), heavy polluting enterprises are more sensitive to air quality changes than light pollution enterprises.
Table10 Heterogeneity analysis of polluting enterprises based on investor sentiment
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
Pollute=1
|
Pollute=0
|
lnCRD
|
Sent
|
lnCRD
|
lnCRD
|
Sent
|
lnCRD
|
Sent
|
|
|
-0.0878**
|
|
|
-0.0648***
|
|
|
|
(-2.4307)
|
|
|
(-4.4319)
|
AQI
|
-0.3266**
|
0.0733**
|
-0.3202**
|
-0.2173***
|
0.0790***
|
-0.2122***
|
|
(-2.4675)
|
(2.2616)
|
(-2.3934)
|
(-6.8103)
|
(4.8337)
|
(-6.6509)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-16.3416***
|
2.9118***
|
-16.0860***
|
-11.8502***
|
2.6578***
|
-11.6779***
|
|
(-9.6838)
|
(3.6270)
|
(-9.4181)
|
(-13.5173)
|
(6.2422)
|
(-13.2420)
|
Observ
|
1,685
|
1,685
|
1,685
|
10,097
|
10,097
|
10,097
|
R-squar
|
0.2356
|
0.0248
|
0.2376
|
0.2639
|
0.0393
|
0.2657
|
Table11 Heterogeneity analysis of polluting enterprises based on government concern
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
Pollute=1
|
Pollute=0
|
lnCRD
|
GS
|
lnCRD
|
lnCRD
|
GS
|
lnCRD
|
GS
|
|
|
-0.0002**
|
|
|
0.0001
|
|
|
|
(-3.0115)
|
|
|
(0.9857)
|
AQI
|
-0.2266**
|
82.9613**
|
-0.2061**
|
-0.2173***
|
12.2183**
|
-0.2184***
|
|
(-2.4675)
|
(2.1959)
|
(-2.2836)
|
(-6.8103)
|
(2.4292)
|
(-6.9294)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-16.3416***
|
-1,158.3991***
|
-16.6283***
|
-11.8502***
|
-608.0354***
|
-11.7974***
|
|
(-9.6838)
|
(-3.4651)
|
(-9.7179)
|
(-13.5173)
|
(-3.8357)
|
(-13.6379)
|
Observ
|
1,685
|
1,685
|
1,685
|
10,097
|
10,097
|
10,097
|
R-squar
|
0.2356
|
0.0303
|
0.2379
|
0.2639
|
0.0045
|
0.2644
|
Air quality, key regulatory enterprises and R&D investment of listed companies
According to the degree of supervision of listed companies, whether listed companies are key regulatory enterprises (Control) is defined as a virtual variable. For key regulatory enterprises, the Control value is 1; for non-key regulatory enterprises, the Control value is 0. Table 12 is the grouped regression result of supervising enterprises with investor sentiment as the intermediary variable, where the models (1)-(3) are the samples of key regulatory enterprises and (4)-(6) are the samples of non-key regulatory enterprises. Both of them have significant intermediary effect, and the intermediary effect of non-key regulatory enterprises is more significant than that of key regulatory enterprises. Table 13 shows the grouped regression results with government concern as the intermediary variable, and the model is set the same as the above. For key regulatory enterprises, government concern does not have a significant intermediary effect, but for non-key enterprises, government concern has a significant intermediary effect, which indicates that key regulatory measures for enterprises can offset the crowding-out effect of government subsidies.
Table12 Heterogeneity analysis of key regulatory enterprises based on investor sentiment
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
Control=1
|
Control=0
|
lnCRD
|
Sent
|
lnCRD
|
lnCRD
|
Sent
|
lnCRD
|
Sent
|
|
|
-0.0746*
|
|
|
-0.0683***
|
|
|
|
(-1.8050)
|
|
|
(-4.5754)
|
AQI
|
-0.3243***
|
0.1271***
|
-0.3148***
|
-0.2010***
|
0.0714***
|
-0.1961***
|
|
(-3.8187)
|
(3.7589)
|
(-3.7136)
|
(-5.6511)
|
(3.7004)
|
(-5.5138)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-12.3399***
|
0.1777
|
-12.3266***
|
-11.1909***
|
3.3082***
|
-10.9651***
|
|
(-6.6044)
|
(0.2459)
|
(-6.5994)
|
(-11.7241)
|
(6.8788)
|
(-11.3830)
|
Observ
|
2,624
|
2,624
|
2,624
|
9,158
|
9,158
|
9,158
|
R-squar
|
0.1610
|
0.0144
|
0.1625
|
0.2479
|
0.0451
|
0.2501
|
Table13 Heterogeneity analysis of key regulatory enterprises based on government concern
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
Control=1
|
Control=0
|
lnCRD
|
GS
|
lnCRD
|
lnCRD
|
GS
|
lnCRD
|
GS
|
|
|
0.0001
|
|
|
-0.0001**
|
|
|
|
(0.9572)
|
|
|
(-2.5112)
|
AQI
|
-0.3243***
|
15.9739
|
-0.3258***
|
-0.2010***
|
27.0198**
|
-0.1992***
|
|
(-3.8187)
|
(0.7800)
|
(-3.8461)
|
(-5.6511)
|
(2.3638)
|
(-5.8071)
|
Control variable
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Cons
|
-12.3399***
|
-441.3144
|
-12.2989***
|
-11.1909***
|
-676.0079***
|
-11.2358***
|
|
(-6.6044)
|
(-1.6432)
|
(-6.5722)
|
(-11.7241)
|
(-3.9024)
|
(-11.8263)
|
Observ
|
2,624
|
2,624
|
2,624
|
9,158
|
9,158
|
9,158
|
R-squar
|
0.1610
|
0.0071
|
0.1614
|
0.2479
|
0.0063
|
0.2482
|
Robustness tests
Endogenous testing
Because there are many factors that affect enterprise R&D Investment, this paper may have the problem of missing variables. In addition, there may be a two-way causality between enterprise R&D investment and air quality, and enterprise R&D investment can improve air quality after achieving the expected benefits. Referring to the related research, this paper selects the two variables of rainfall and relative humidity as the instrumental variables of air pollution (Xie and Lin, 2020). The results of the instrumental variable method show that the relevant conclusions of this paper are still valid (As shown in Table 14).
Table 14
Regression results of the instrumental variable method
Variable name
|
lnCRD
|
lnCRP
|
AQI
|
-0.2137***
|
-0.0433*
|
|
(-7.3404)
|
(-1.8654)
|
Cons
|
-12.5545***
|
-6.3412***
|
|
(-16.2045)
|
(-13.5546)
|
Control variable
|
Yes
|
Yes
|
Observ
|
11,782
|
11,782
|
Weak tool variable test
|
Pass
|
Pass
|
Exogeneity test
|
Pass
|
Pass
|
Variable substitution test
In order to ensure the robustness of the results of this paper, in addition to the explained variables represented by R&D investment and R&D personnel investment, this paper also replaces the technical complexity of the control variable (large class) with the technical complexity of the small class (TCD0). At the same time, the investor sentiment (Sent) is replaced by the cumulative monthly return Sent0, which is 6 months behind the first period and does not consider the cash dividend. As shown in Table 15, the conclusions of this paper are still valid.
Table 15
Regression results of the variable substitution method
Variable
|
(1)
|
(2)
|
(3)
|
(4)
|
(5)
|
(6)
|
lnCRD
|
Sent0
|
lnCRD
|
lnCRD
|
GS
|
lnCRD
|
Sent0
|
|
|
-0.0639***
|
|
|
|
|
|
|
(-4.7554)
|
|
|
|
AQI
|
-0.2208***
|
0.0977***
|
-0.2052***
|
-0.2208***
|
23.6507***
|
-0.2219***
|
|
(-7.2137)
|
(6.5333)
|
(-6.8086)
|
(-7.2137)
|
(3.5218)
|
(-7.3686)
|
GS
|
|
|
|
|
|
0.0001***
|
|
|
|
|
|
|
(4.4442)
|
Constant
|
-12.3011***
|
2.9687***
|
-12.1011***
|
-12.3011***
|
-644.9894***
|
-12.2698***
|
|
(-15.1678)
|
(7.5399)
|
(-14.7955)
|
(-15.1678)
|
(-4.4346)
|
(-15.2665)
|
Observ
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
11,782
|
R-squared
|
0.2551
|
0.0639
|
0.2581
|
0.2551
|
0.0100
|
0.2552
|