Revisiting the shape of the yield curve: the effect of interest rate volatility.

This paper examines the relationship between interest-rate volatility and the shape of the yield curve. The yield curve is parsimoniously described by its level, slope, and curvature. The level, the slope and the curvature are analyzed within a trivariate heteroskedastic model, where the conditional short-rate volatility is included in the mean specification. The slope and the curvature depend positively and significantly on the short-rate volatility. The effect of the interest rate volatility is more pronounced for the curvature than for the slope. Differences between subperiods are explored, as are differences across the maturity spectrum.