Arbeitspapier

Consumption decision, portfolio choice and healthcare irreversible investment

We propose a tractable dynamic framework for the joint determination of optimal consumption, portfolio choice, and healthcare irreversible investment. Our model is based on a Merton's portfolio and consumption problem, where, in addition, the agent can choose the time at which undertaking a costly lump sum health investment decision. Health depreciates with age and directly affects the agent's mortality force, so that investment into healthcare reduces the agent's mortality risk. The resulting optimization problem is formulated as a stochastic control-stopping problem with a random time-horizon and state-variables given by the agent's wealth and health capital. We transform this problem into its dual version, which is now a two-dimensional optimal stopping problem with interconnected dynamics and finite time-horizon. Regularity of the optimal stopping value function is derived and the related free boundary surface is proved to be Lipschitz continuous and it is characterized as the unique solution to a nonlinear integral equation. In the original coordinates, the agent thus invests into healthcare whenever her wealth exceeds an age- and health-dependent transformed version of the optimal stopping boundary.

Language
Englisch

Bibliographic citation
Series: Center for Mathematical Economics Working Papers ; No. 671

Classification
Wirtschaft
Portfolio Choice; Investment Decisions
Macroeconomics: Consumption; Saving; Wealth
Health Insurance, Public and Private
Subject
Optimal timing of health investment
Optimal consumption
Optimal portfolio choice
Duality
Optimal stopping
Free boundary
Stochastic control

Event
Geistige Schöpfung
(who)
Ferrari, Giorgio
Zhu, Shihao
Event
Veröffentlichung
(who)
Bielefeld University, Center for Mathematical Economics (IMW)
(where)
Bielefeld
(when)
2022

Handle
URN
urn:nbn:de:0070-pub-29675370
Last update
10.03.2025, 11:43 AM CET

Data provider

This object is provided by:
ZBW - Deutsche Zentralbibliothek für Wirtschaftswissenschaften - Leibniz-Informationszentrum Wirtschaft. If you have any questions about the object, please contact the data provider.

Object type

  • Arbeitspapier

Associated

  • Ferrari, Giorgio
  • Zhu, Shihao
  • Bielefeld University, Center for Mathematical Economics (IMW)

Time of origin

  • 2022

Other Objects (12)