Starting with the normalized quadratic expenditure function, linear and quadratic spline models are introduced theoretically and are empirically estimated using Japanese consumer data for four goods ...

For varying-coefficient models, it is often of interest to test whether coefficient functions are time varying or time invariant. We propose a unified and efficient nonparametric hypothesis testing ...

A piecewise affine (PWA) model of a gene regulatory network is considered. After an introduction to the model, the problem of finding a generally non-smooth function V (x) which is non increasing ...