Computer program to analyze directional data, based on the methods of Fisher and Watson

Abstract

Based on the methods of Fisher and Watson, FORTRAN IV computer programs are presented for the following analyses of directional observations on the sphere: (1) to determine if points are randomly distributed; (2) to estimate the azimuth and inclination of the center (mean direction) of a chtster and to estimate the precision (closeness) with which points are clustered," (3) to determine if two or more clusters have the same mean direction; (4) to determine if two clusters have the same precision of clustering; and (5) to locate the pole of a great-circle girdle of pohzts. Limitations of these analyses for undirected directional observations on the hemi-sphere also are given.

Directional Data Analysis

“…Clearly in a diagnostic situation, words like approximately equal, small, and large are not precisely defined. The program by Schuenemeyer, Koch, and Link (1972) computes these and other cluster statistics. This result appears to be reasonable even though the eigenvalues differ in size from each other.…”