The arithmetic mean expectation model is not able to measure the income of portfolio investment correctly as bonds are a kind of successive investment, but the geometric average expectation can measure the income of successive investment.

• 摘要由于证券是一种连续投资，算术平均收益率并不能完全反映投资的收益情况，而几何平均期望收益率才能反映连续投资的实际收益。