Table 4. IV Poisson GMM with VCE(Robust).
| Variable | Model (1) | Model (2) | Model (3) | Model (4)a | Model (5) |
|---|---|---|---|---|---|
| Independent Variables | |||||
| Collab.Innov. | 0.0015 (0.0008) |
||||
| Firm-University | 0.0035* (0.0014) |
||||
| Firm-GRI | -0.0012 (0.0026) |
||||
| Inter-firm | 0.0214*** (0.0053) |
||||
| Inter-ICT firm | 0.0697** (0.0258) |
||||
| Control Variables | |||||
| Ln(FirmSize) | 0.4564*** (0.1167) |
0.4780*** (0.1093) |
0.4928*** (0.1260) |
(Omitted) | 0.4713*** (0.1112) |
| Ln(R&D Exp.) | 0.4193*** (0.0552) |
0.4010*** (0.0553) |
0.4349*** (0.0654) |
0.5905*** (0.0401) |
0.3390*** (0.0630) |
| Ln(Productivity) | -0.2569 (0.1739) |
-0.2362 (0.1711) |
-0.2467 (0.1814) |
-0.4093** (0.1526) |
-0.1806 (0.1690) |
| Conglomerate Affiliates | 0.0428 (0.1422) |
0.0432 (0.1413) |
0.0266 (0.1420) |
0.1448 (0.1340) |
0.0502 (0.1406) |
| Firm Age | -0.0299* (0.0125) |
-0.0317* (0.0124) |
-0.0313* (0.0130) |
(Omitted) | -0.0343* (0.0137) |
| Large Firms | 0.5498*** (0.1429) |
0.5552*** (0.1387) |
0.4631** (0.1482) |
0.9089*** (0.1211) |
0.6661*** (0.1502) |
| IPO | -1.0111*** (0.2405) |
-0.9055*** (0.2336) |
-0.8666*** (0.2258) |
-0.9001*** (0.1931) |
-0.8569*** (0.2417) |
| Year | 0.0728*** (0.0128) |
0.0711*** (0.0125) |
0.0666*** (0.0131) |
0.0513** (0.0176) |
0.0801*** (0.0139) |
| Constant | -151.0886*** (25.2727) |
-147.6601*** (24.6526) |
-138.9578*** (25.7383) |
-106.5242** (34.6730) |
-165.6213*** (27.5088) |
| Observations | 6,851 | 6,851 | 6,851 | 6,851 | 6,851 |
| Weak IV Test | 152.18 | 372.36 | 77.69 | 264.40 | 233.65 |
Note:
* p<0.05;
** p<0.01;
*** p<0.001;
Standard errors in parentheses.
a Model (4) cannot be estimated because the Hessian is not positive semidefinite. Therefore, it is estimated excluding the Ln(FirmSize) and Firm Age variables.