Abstract
The problem of maximizing expected utility of final wealth in an incomplete market is investigated. The incomplete market is modelled by a bond and a finite number of stocks, the latter being driven by a d-dimensional Brownian motion. The coefficients of the bond and stock price processes are adapted to this Brownian motion, and the number of stocks is less than or equal to the dimension of the driving Brownian motion. It is shown that there is a way to “fictitiously” complete this market so that the optimal protfolio for the resulting completed market coincides with the optimal portfolio for the original incomplete market. A number of equivalent characterizations of the fictitious completion are given, and examples are provided.
Research supported by the National Science Foundation under Grant DMS-87-23078.
Research supported by the National Science Foundation under Grant DMS-87-02537.
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Section 10. References
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Karatzas, I., Lehoczky, J.P., Shreve, S.E., Xu, GL. (1990). Optimality conditions for utility maximization in an incomplete market. In: Bensoussan, A., Lions, J.L. (eds) Analysis and Optimization of Systes. Lecture Notes in Control and Information Sciences, vol 144. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0120024
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DOI: https://doi.org/10.1007/BFb0120024
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