This paper examines statistical approaches for interpolating climatic data over large regions, providing a brief introduction to interpolation techniques for climate variables of use in agricultural research, as well as general recommendations for future research to assess interpolation techniques. Three approaches—1) inverse distance weighted averaging (IDWA), 2) thin plate smoothing splines a...

The goal of this paper is to provide a statistically based deenition of employment subcenters for multicentric urban areas. In particular, we examine the shape of the employment density function using quantile smoothing splines as a nonparametric empirical speciication. This approach allows inspection of the employment gradient at the upper tail rather than the center of the employment density ...

We develop a variance reduction method for smoothing splines. We do this by showing that the quadratic interpolation method introduced in Cheng et al. (2006), for local linear estimators, also works for smoothing splines. For a given point of estimation, Cheng et al. (2006) define a variance-reduced local linear estimate as a linear combination of classical estimates at three nearby points. We ...

In this paper a recursive control theoretic smoothing spline approach is proposed for reconstructing a closed contour. Periodic splines are generated through minimizing a cost function subject to constraints imposed by a linear control system. The optimal control problem is shown to be proper and sufficient optimality conditions are derived for a special case of the problem using Hamilton-Jacob...

Vector field reconstruction is a problem that arises in many scientific applications. In this paper we study a div-curl approximation of vector fields by pseudo-polyharmonic splines and elastic splines. This leads to the variational smoothing and interpolating spline problems with minimization of an energy involving the rotational and the divergence of the vector field.

A T-mesh is basically a rectangular grid that allows T-junctions. Recently, Deng etal introduced splines over T-meshes, which are generalizations of T-splines invented by Sederberg etal, and proposed a dimension formula based on the B-net method. In this paper, we derive an equivalent dimension formula in a different form with the smoothing cofactor method. Mathematics subject classification: