1. A note on P- vs. Q-expected loss portfolio constraints
- Author
-
Jia-Wen Gu, Mogens Steffensen, and Harry Zheng
- Subjects
Mathematics, Interdisciplinary Applications ,Economics ,Measure (physics) ,Social Sciences ,Business economics ,Risk-neutral measure Q ,Business & Economics ,0502 economics and business ,Econometrics ,050207 economics ,01 Mathematical Sciences ,14 Economics ,Consumption (economics) ,Optimal Portfolio ,Q-strategy fulfilling P-risk constraint ,Expected loss constraint ,050208 finance ,Science & Technology ,Physical measure P ,15 Commerce, Management, Tourism and Services ,05 social sciences ,CONSUMPTION ,POLICIES ,Social Sciences, Mathematical Methods ,Physical measure ,Risk-neutral measure ,Business, Finance ,strategy fulfilling -risk constraint ,Physical Sciences ,Benchmark (computing) ,Portfolio ,Portfolio optimization ,General Economics, Econometrics and Finance ,Expected loss ,Mathematics ,Mathematical Methods In Social Sciences ,Finance - Abstract
We consider portfolio optimization problems with expected loss constraints under the physical measure (Formula presented.) and the risk neutral measure (Formula presented.), respectively. Using Merton's portfolio as a benchmark portfolio, the optimal terminal wealth of the (Formula presented.) -risk constraint problem can be easily replicated with the standard delta hedging strategy. Motivated by this, we consider the (Formula presented.) -strategy fulfilling the (Formula presented.) -risk constraint and compare its solution with the true optimal solution of the (Formula presented.) -risk constraint problem. We show the existence and uniqueness of the optimal solution to the (Formula presented.) -strategy fulfilling the (Formula presented.) -risk constraint, and provide a tractable evaluation method. The (Formula presented.) -strategy fulfilling the (Formula presented.) -risk constraint is not only easier to implement with standard forwards and puts on a benchmark portfolio than the (Formula presented.) -risk constraint problem, but also easier to solve than either of the (Formula presented.) - or (Formula presented.) -risk constraint problem. The numerical test shows that the difference of the values of the two strategies (the (Formula presented.) -strategy fulfilling the (Formula presented.) -risk constraint and the optimal strategy solving the (Formula presented.) -risk constraint problem) is reasonably small.
- Published
- 2020
- Full Text
- View/download PDF