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arXiv · 1605.01028

On Optimal Retirement (How to Retire Early)

Philip Ernst·Dean Foster·Larry Shepp
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Abstract

We pose an optimal control problem arising in a perhaps new model for retirement investing. Given a control function $f$ and our current net worth as $X(t)$ for any $t$, we invest an amount $f(X(t))$ in the market. We need a fortune of $M$ "superdollars" to retire and want to retire as early as possible. We model our change in net worth over each infinitesimal time interval by the Ito process $dX(t)= (1+f(X(t))dt+ f(X(t))dW(t)$. We show how to choose the optimal $f=f_0$ and show that the choice of $f_0$ is optimal among all nonanticipative investment strategies, not just among Markovian ones.

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Philip Ernst, Dean Foster, Larry Shepp. 2016-05-03. On Optimal Retirement (How to Retire Early). https://arxiv.org/abs/1605.01028

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