The Determinants of Full-Empty Truck Movements

A model is developed to explain full-empty movement decisions for motor carriers. The model is estimated for movements to Florida of carriers serving the Florida produce/ornamentals industry. The results indicate that carriers act rationally, basing their decisions on a wide range of factors. The findings also suggest that regulatory restrictions continue to result in unnecessary empty movements. Key words: exempt trucking, logit, regulations, search theory. Transportation rates playa crucial role in the determination of economic activity over time and space. Despite this fact, relatively little attention has been devoted to understanding transportation markets. Indeed, it is common in interregional trade modeling to treat trans-portation supply as perfectly elastic. This tangential treatment of transportation markets has been identified as a major reason for the failure of many, if not most, interregional trade models to reflect adequately the eco-nomic activity being depicted (Johnson, p. 63). This article describes a study which fo-cuses on understanding one aspect of these markets: the determinants of full/empty move-ment decisions. The results help to explain seasonal swings in rate levels, why some rates taper (i.e., increase at a decreasing rate) with distance, the impact of regulatory controls, and the role of expectations in carrier decision making. It is recognized that jointness in the produc-tion of transportation services favors full movements. If a vehicle goes from point ito pointj, the marginal cost of obtaining and car-rying a load is the cost of search, pickup, and delivery, and the increment in fuel and labor costs over those for running empty (Mohring, pp. 59-74). This increment is generally small when compared to total running costs. There