股票数目n | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
方差 | 9.382 | 5.094 | 3.531 | 2.896 | 2.636 | 2.435 | 2.312 | 1.961 | 1.958 |
股票数目n | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
方差 | 1.836 | 1.836 | 1.833 | 1.833 | 1.833 | 1.833 | 1.832 | 1.832 | 1.832 |