Ever wonder what sorts of errors freshman math students make? There are a couple of pretty basic ones.

Many data are suitably modeled by functions consisting of straight-line segments. These functions may be called piecewise-linear. Smooth functions that are related to the hyperbola and that have ...

Three families of models for the covariance function are discussed: multivariate, autoregressive, and random effects. Illustrations demonstrate the flexibility and utility of the proposed approach to ...

If the observed phenotype yn does not require a transformation, only the linear term will be used. Otherwise, the function will consist of both the linear term and one or more step functions.