Those gravity parameters again

Abstract

Curry L., Griffith D. A. and Sheppard E. S. (1975) Those gravity parameters again, Reg. Studies 9, 289–296. The arguments presented in a recent paper by Cliff et al. (1974) as regards the relation between gravity parameters and map pattern are reassessed. First, the experimental simulation model designed to support their assertions is examined and found wanting in several fundamental aspects. Second, their statistical argument is evaluated, and it is concluded that when attention is concentrated on specification and interpretation of the parameters rather than on bias in their estimates, then the gravity specification does indeed confound spatial interaction and spatial structure.