Citation

Parish DJ. Proc. IRCOBI 1975; 3: 214-224.

Copyright

(Copyright © 1975, International Research Council on Biomechanics of Injury)

DOI

unavailable

PMID

unavailable

Abstract

In this effort to suggest a possible explanation for the predictive failure of current models, concepts from economic theory, particularly the theory of consumption function are utilized, and criticisms (which are equally applicable to all category analysis models for predicting car ownership) are directed at the procedures used in the original National Traffic Model. It is suggested that the problem lies in the way in which the regression equations relating phoc (proportion of households owning cars) to household income are derived. The paper concludes that a model of car ownership based on permanent disposable income may prove more successful than one based on gross actual income. It is observed that current models may considerably underestimate the sensitivity of car ownership to income.