| 变量 | 样本量（个） | 均值 | 标准差 | 最小值 | 最大值 |
|---|---|---|---|---|---|
| Digital | 7509 | 2.183 | 1.351 | 0.000 | 6.068 |
| Distance | 7509 | 32.270 | 37.205 | 0.163 | 149.983 |
| Density | 7509 | 2.645 | 0.868 | 0.693 | 5.697 |
| Dual | 7406 | 0.305 | 0.461 | 0.000 | 1.000 |
| SOE | 7509 | 0.292 | 0.455 | 0.000 | 1.000 |
| Cash | 7509 | 0.043 | 0.071 | -0.650 | 0.874 |
| Size | 7509 | 22.402 | 1.423 | 17.954 | 31.138 |
| Age | 7509 | 2.878 | 0.348 | 1.099 | 3.989 |
| Board | 7506 | 2.118 | 0.209 | 1.386 | 2.890 |
| R&D | 7509 | 9.998 | 1.161 | 3.466 | 11.791 |
| Univ | 7509 | 4.680 | 0.372 | 1.946 | 5.118 |
