长期风险:一种算子方法

Long-Term Risk: An Operator Approach

Econometrica · 2008
被引 282
人大 A+FT50ABS 4*

中文导读

通过研究估值算子族的特征值和特征函数,揭示了非线性连续时间马尔可夫环境下的长期风险-收益关系,为理解现金流增长与风险调整的长期权衡提供了分析框架。

Abstract

We create an analytical structure that reveals the long-run risk-return relationship for nonlinear continuous-time Markov environments. We do so by studying an eigenvalue problem associated with a positive eigenfunction for a conveniently chosen family of valuation operators. The members of this family are indexed by the elapsed time between payoff and valuation dates, and they are necessarily related via a mathematical structure called a semigroup. We represent the semigroup using a positive process with three components: an exponential term constructed from the eigenvalue, a martingale, and a transient eigenfunction term. The eigenvalue encodes the risk adjustment, the martingale alters the probability measure to capture long-run approximation, and the eigenfunction gives the long-run dependence on the Markov state. We discuss sufficient conditions for the existence and uniqueness of the relevant eigenvalue and eigenfunction. By showing how changes in the stochastic growth components of cash flows induce changes in the corresponding eigenvalues and eigenfunctions, we reveal a long-run risk-return trade-off.

长期风险算子方法特征值风险收益权衡