| Abstract: | A history of the development of shape indices, going back to some of the earliest formulas proposed by German scholars in the 19th century, groups the various measures in terms of the initial set of data used in their derivation. The author does not approve of indices derived from the perimeter and area of a figure (such as Chorley's lemniscate), linear dimensions and area (Gibbs, Haggett), inscribing and circumscribing circles (Penck, Krumbein), tangential contours and from radial vectors (Boyce and Clark). The author sees greater promise in approaches using the distance from elements of the figure to the perimeter, Bunge's inscribed polygons, and the distance from elements of the figure to the center (Thünen, Blair and Biss). Further work on shape indices is urged with a view to deriving measures that would reflect not only compactness, but also the degree of dissection and contour indentation. The problem is assuming greater significance in light of advances made in picture recognition and processing by computer. |
