| (1) | (2) | (3) | (4) | (5) |
变量 | 数量 | 平均值 | 标准差 | 最小值 | 最大值 |
rd | 1780 | 4.674 | 3.449 | 0 | 45.04 |
patent | 1780 | 2.649 | 1.307 | 0 | 8.918 |
inc | 1780 | 0.835 | 0.371 | 0 | 1 |
HHI_C | 1780 | 0.0538 | 0.0435 | 0.0140 | 0.249 |
roa | 1780 | 0.0488 | 0.0560 | −0.860 | 0.275 |
fix | 1780 | 0.459 | 0.522 | 0.0127 | 16.92 |
size | 1780 | 21.89 | 1.108 | 19.59 | 26.25 |
lev | 1780 | 0.370 | 0.186 | 0.0111 | 1.070 |
age | 1780 | 2.715 | 0.362 | 1.386 | 3.871 |
dirnum | 1780 | 2.119 | 0.180 | 1.386 | 2.833 |
irrnum | 1780 | 0.374 | 0.0552 | 0.250 | 0.714 |