The profit rate, investment risk and transaction cost are synthetically considered in this new model, which is very useful in the portfolio selection.

在本模型中综合考虑了证券组合的收益，风险，交易费用等因素，对投资者选择有效证券组合有一定的实用价值。

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In the early 1950s, another doctoral student named Harry Markowitz posited a statistical approach to investment selection called Modern Portfolio Theory.

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The active manager claims that through either market timing or individual security selection he can add value to your investment portfolio in excess of his costs.

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In a 1952 paper and 1959 book, Portfolio Selection, future Nobel laureate Harry Markowitz expounded MPT for the investment world.

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