Smoothing Spatial Data by Estimating Mean Local Variance.
Abstract
A nearest neighbor nonparametric regression method is used to estimate air pollution levels at other than measured points. The method requires an appropriate smoother. Cross-validation is used to determine the appropriate smoother. An alternative method is introduced to determine an appropriate level of smoothing which involves minimizing mean local variance. Mean local variance is a function of the size of a circular window. It is minimized for two pollutants in Ohio, New York and Florida. The smoother obtained by cross-validation using Ohio's data is compared to that obtained by minimizing mean local variance. Keywords: Air quality; Sulfur dioxide; Suspended particulates; Statistical data; Pollution concentrations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1988
- Accession Number
- ADA195302
Entities
People
- Laura D. Johnson
Organizations
- Naval Postgraduate School