Translator Disclaimer
1 November 2008 Effects of Point Pattern Shape on Home-Range Estimates
Joni A. Downs, Mark W. Horner
Author Affiliations +

Home-range estimators are commonly tested with simulated animal locational data in the laboratory before the estimators are used in practice. Although kernel density estimation (KDE) has performed well as a home-range estimator for simulated data, several recent studies have reported its poor performance when used with data collected in the field. This difference may be because KDE and other home-range estimators are generally tested with simulated point locations that follow known statistical distributions, such as bivariate normal mixtures, which may not represent well the space-use patterns of all wildlife species. We used simulated animal locational data of 5 point pattern shapes that represent a range of wildlife utilization distributions to test 4 methods of home-range estimation: 1) KDE with reference bandwidths, 2) KDE with least-squares cross-validation, 3) KDE with plug-in bandwidths, and 4) minimum convex polygon (MCP). For the point patterns we simulated, MCP tended to produce more accurate area estimates than KDE methods. However, MCP estimates were markedly unstable, with bias varying widely with both sample size and point pattern shape. The KDE methods performed best for concave distributions, which are similar to bivariate normal mixtures, but still overestimated home ranges by about 40–50% even in the best cases. For convex, linear, perforated, and disjoint point patterns, KDE methods overestimated home-range sizes by 50–300%, depending on sample size and method of bandwidth selection. These results indicate that KDE does not produce home-range estimates that are as accurate as the literature suggests, and we recommend exploring other techniques of home-range estimation.

Joni A. Downs and Mark W. Horner "Effects of Point Pattern Shape on Home-Range Estimates," Journal of Wildlife Management 72(8), 1813-1818, (1 November 2008).
Published: 1 November 2008

This article is only available to subscribers.
It is not available for individual sale.

home range
Kernel Density Estimation
least-squares cross-validation
minimum convex polygon
plug-in bandwidth selection
point patterns
Get copyright permission
Back to Top