A Note on Relaxed Gravity Models

Abstract

Relaxed gravity models, that is, gravity models with upper and lower bounds on the marginal totals, often have solutions with the property that the upper or lower bounds are satisfied with equality for most marginal totals. In this paper modifications are presented for the relaxed gravity models, which overcome this unwanted model property. The paper contains illustrative examples with data from the county of Östergötland, Sweden.