Looking Forward to Backward-Looking Rates: A Modeling Framework for Term Rates Replacing LIBOR

Abstract

In this paper, we define and model forward risk-free term rates, which appear in the payoff definition of derivatives, and possibly cash instruments, based on the new interest-rate benchmarks that will be replacing IBORs globally. We show that the classical interest rate modeling framework can be naturally extended to describe the evolution of both the forward-looking (IBOR-like) and backward-looking (setting-in-arrears) term rates using the same stochastic process. In particular, we show that the extension of the popular LIBOR Market Model (LMM) to the backward-looking rates completes the model by providing additional information about the rate dynamics not accessible in the LMM.

Keywords: IBOR replacement, RFR, SOFR, LMM, market model, forward rates

JEL Classification: C22, C60, G12, G13