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butions for the simulated home ranges. Seaman chose points randomly within
the simulated home ranges, simulating the collection of telemetry or trapping
or sighting location data, and then he estimated the simulated home ranges
from the “location” data points. He then compared the kernel estimators to
the harmonic mean estimator because the harmonic mean estimator was
widely used into the early 1990s, it appeared preferable to most well-known
nonkernel estimators (Boulanger and White 1990), and Seaman's comparisons
can be extrapolated to other home range estimators through Boulanger and
White's (1990) results. Seaman found that the different home range estimators
varied greatly in accuracy of estimating both home range areas and utility dis-
tributions (figure 3.4).
The fixed kernel estimator, using cross-validation to choose band width,
A
D
B
E
C
F
Figure 3.4
A complex, simulated home range. (A) True density contours. (B) Fixed kernel density
estimate with cross-validated band width choice. (C) Adaptive kernel density estimate with cross-
validated band width choice. (D) Fixed kernel density estimate with ad hoc band width choice.
(E) Adaptive kernel density estimate with ad hoc band width choice. (F) Harmonic mean estimate.
Modified from Powell et al. (1997).
