Description: This article focuses on one fundamental modeling assumption — the choice of a benchmark rate or risk-free rate. The author looks at this bond market assumption as a case study of how one needs to monitor fundamental market changes for their impact on assumptions.

Description: This article, with some humor, describes a movement known as “econophysics” of physicists modeling economic systems, including capital markets, using techniques and concepts developed in studying the out-of-equilibrium dynamics of complex systems. A version of this article appeared in The Actuary UK in August 2004. Reprinted with permission.