A FAMILY OF RELAXED SPATIAL INTERACTION MODELS

In traditional, constrained spatial interaction models, the number of predicted movers leaving origins and entering destinations is constrai ned to match exactly the observed number. In relaxed models, these con straints are allowed to vary over a range of values in order to provid e greater flexibility in calibration. This paper identifies a new, sev en-member family of relaxed spatial interaction models, based upon the generalization of the constraint sets used in model derivation. Three categories are suggested, including single and doubly relaxed models, cost-relaxed models, and totally relaxed models. This paper introduce s these relaxed models as entropy-maximizing ones, proposes a terminol ogy for them, and describes empirical situations in which they are use ful.