| 变量 | Entry | Maintain | |||
|---|---|---|---|---|---|
| low-complexity (1) | high-complexity (2) | low-complexity (3) | high-complexity (4) | ||
| Migration | 0.0351***(0.0109) | 0.0546***(0.0069) | 0.0582***(0.0188) | 0.0454***(0.0128) | |
| Density | 12.9930***(0.1975) | 12.4044***(0.1572) | 15.7067***(0.3184) | 13.9160***(0.2491) | |
| Migration×Density | -0.1193***(0.0323) | -0.2358***(0.0213) | -0.1990***(0.0497) | -0.1419***(0.0343) | |
| Trade | -0.0190(0.0117) | -0.0290***(0.0067) | -0.0295*(0.0166) | -0.0288**(0.0117) | |
| FDI | 0.0663(0.0433) | 0.0249(0.0186) | 0.0684(0.0690) | -0.0440(0.0272) | |
| Total_pat | 0.1420***(0.0106) | 0.0717***(0.0051) | 0.1057***(0.0104) | 0.0733***(0.0093) | |
| “国家—时段”控制 | YES | YES | YES | YES | |
| “技术—时段”控制 | YES | YES | YES | YES | |
| N | 7187 | 9946 | 3867 | 4494 | |
| R2 | 0.580 | 0.575 | 0.650 | 0.676 | |
