We derive the class of arbitrage-free affine dynamic term structure models that approximate the widely-used Nelson-Siegel yield-curve specification. Our theoretical analysis relates this new class of models to the canonical representation of the three-factor arbitrage-free affine model. Our...

This paper presents a portfolio model of asset price effects arising from large-scale asset purchases by central banks — commonly known as quantitative easing (QE). Two financial frictions, segmentation of the market for central bank reserves and imperfect asset substitutability, give rise to...

The Svensson generalization of the popular Nelson-Siegel term structure model is widely used by practitioners and central banks. Unfortunately, like the original Nelson-Siegel specification, this generalization, in its dynamic form, does not enforce arbitrage-free consistency over time. Indeed,...