A mathematical function is a formula that takes an input, x, applies a set of calculations to it, and produces an output called y. By calculating a function at a large number of set intervals, it is ...

For space-time processes on global or large scales, it is critical to use models that respect the Earth's spherical shape. The covariance functions of such processes should be not only positive ...

This work considers a number of properties of space-time covariance functions and how these relate to the spatial-temporal interactions of the process. First, it examines how the smoothness away from ...