اثرات بازار کار در ارزیابی هزینه ها و مزایای قیمت گذاری جاده

Traffic congestion and the policies used to combat it have been studied extensively. One area which has received less attention is the secondary impacts of such policies. This paper uses a micro-simulation framework to study the effect on labour markets of road pricing. The key benefit of our chosen methodology is that it allows a simultaneous consideration of both commuting and migration decisions. We show that while welfare gains can be achieved through optimal charging, this may come at the price of decreased integration. This may manifest through either greater centralisation tendencies in population, or through unemployment disparities between regions.

With the global growth in car use, infrastructure is becoming an increasingly scarce commodity. For example, Schrank et al. (2010) of the Texas Transportation Institute estimated that the annual cost of congestion to the US economy in 2009 was around US$115 bn. This presents a significant challenge to policy makers. A number of options are available. Supply can be increased, although this can be costly and may induce fresh demand (Small and Verhoef, 2007, p.176), or demand can be managed. The introduction of full marginal cost road pricing is one way to reduce demand. The principal is well understood theoretically and has been studied extensively empirically (Winston and Langer, 2006). The problem of traffic congestion has many dimensions. Policy makers must consider distributional, environmental, efficiency and political factors. All of these aspects have received attention in the literature. However, one area which is usually neglected is the effect on the labour market. Transport infrastructure and policy can have serious effects on flows of commuters, migrants and on the distribution of unemployment. For example, in a study of highway investment Winston and Langer (2006) choose to ignore what they call ‘second order effects’, by which they mean labour market outcomes. Eliasson (2009) conducts a cost benefit analysis of congestion charging in Sweden but makes no reference to labour market effects. Graham and Glaister (2006) consider the spatial impacts of congestion pricing but also neglect the implications for regional disparities.

This paper has extended the existing literature on road pricing by focusing on the labour market effects of road pricing in a situation where migration and commuting decisions have been modelled simultaneously. The aim was to understand how migration and commuting flows were affected by the introduction of an optimal congestion charge. Section 4 showed that the congestion charge relied on creating some kind of disparity in order to effect an improvement in aggregate utility. This is since socially inefficient commuters either migrate or become unemployed. The split between these two depends on several factors. The experiments presented in this paper explored the effect of distance on the split and showed that shorter distances were associated with higher migration while unemployment disparities were more likely to occur when distances between regions are large.