Dreaming of Freedom in the Americas: Four Minds and A Name

The full text of the inaugural lecture of the Institute for the Study of the Americas, given by Professor James Dunkerley on 25 October 2004

Magnesium-lithium alloys developed for low temperature use

Three new magnesium-lithium alloys have been developed for application at cryogenic temperatures. These lightweight alloys have approximately doubled the tensile and yield strengths at room temperature of previously described magnesium-lithium alloys

What drives gasoline taxes?.

Gasoline taxes are the most important tax on car use. The question naturally arises as to what tax would be adopted by a government that responds to the preferences of the public. To address that issue, we begin with the standard Downsian model, where policy is determined by the median voter. This model predicts that as long as the median voter is not a car user, he wants high taxes on road use and a road capacity that maximizes net tax revenues. When he becomes a driver himself, he wants road user taxes that are lower and only increase to control congestion, as well as more road capacity. We then use panel data for 28 countries and find support for our theory. When the median voter becomes a driver, the gasoline tax drops on average by 20%.

What Drives Gasoline Prices?

Gasoline taxes are the most important tax on car use. The question naturally arises as to what tax would be adopted by a government that responds to the preferences of the public. To address that issue, we begin with the standard Downsian model, where policy is determined by the median voter. This model predicts that as long as the median voter is not a car user, he wants high taxes on road use and a road capacity that maximizes net tax revenues. When he becomes a driver himself, he wants road user taxes that are lower and only increase to control congestion, as well as more road capacity. We then use panel data for 28 countries and find support for our theory. When the median voter becomes a driver, the gasoline tax drops on average by 20%.Gasoline taxes; Median voter theory; Political economy

What drives gasoline taxes?

Gasoline taxes are the most important tax on car use. The question naturally arises as to what tax would be adopted by a government that responds to the preferences of the public. To address that issue, we begin with the standard Downsian model, where policy is determined by the median voter. This model predicts that as long as the median voter is not a car user, he wants high taxes on road use and a road capacity that maximizes net tax revenues. When he becomes a driver himself, he wants road user taxes that are lower and only increase to control congestion, as well as more road capacity. We then use panel data for 28 countries and find support for our theory. When the median voter becomes a driver, the gasoline tax drops on average by 20%.gasoline taxes, median voter theory, political economy

The interactin between tolls and capacity investment in serial and parallel transport networks

The purpose of this paper is to compare the interaction between pricing and capacity decisions on simple serial and parallel transport networks. When individual links of the network are operated by different regional or national authorities, toll and capacity competition is likely to result. Moreover, the problem is potentially complicated by the presence of both local and transit demand on each link of the network. We bring together and extend the recent literature on the topic and, using both theory and numerical simulation techniques, provide a careful comparison of toll and capacity interaction on serial and parallel network structures. First, we show that there is more tax exporting in serial transport corridors than on competing parallel road networks. Second, the inability to toll transit has quite dramatic negative welfare effects on parallel networks. On the contrary, in serial transport corridors it may actually be undesirable to allow the tolling of transit at all. Third, if the links are exclusively used by transit transport, toll and capacity decisions are independent in serial networks. This does not generally hold in the presence of local transport. Moreover, it contrasts with a parallel setting where regional authorities compete for transit; in that case, regional investment in capacity leads to lower Nash equilibrium tolls.congestion pricing, transport investment, transit traffic

Strategic investment and pricing decisions in a congested transport corridor.

This paper studies pricing and investment decisions on a congested transport corridor where the elements of the corridor are controlled by different governments. A corridor can be an interstate highway or railway line, or an inter-modal connection. We model the simplest corridor: two transport links in series, where each of the links is controlled by a different government. Each link is used by transit as well as by local traffic; both links are subject to congestion. We consider a two stage noncooperative game where both governments strategically set capacity in the first stage and play a pricing game in the second stage. Three pricing regimes are distinguished: (i) differentiated tolls between local and transit transport, (ii) one uniform toll on local and transit traffic, and (iii) only the local users can be tolled. Numerical analysis illustrates all theoretical insights. A number of interesting results are obtained. First, transit tolls on the network will be inefficiently high. If only local traffic can be tolled, however, the Nash equilibrium tolls are inefficiently low. Second, raising the toll on transit through a given country by one euro raises the toll on the whole trajectory by less than one euro. Third, higher capacity investment in a given region not only reduces optimal tolls in this region under all pricing regimes but it also increases the transit tolls on the other link of the corridor. Fourth, capacities in the different regions are strategic complements: when one country on the corridor increases transport capacity, it forces the other country to do the same. Fifth, we find interesting interactions between optimal capacities and the set of pricing instruments used: capacity with differentiated tolls is substantially higher than in the case of uniform tolls but overall welfare is lower. Finally, if transit is sufficiently important, it may be welfare improving not to allow any tolling at all, or to only allow the tolling of locals.Investment; Pricing; Decisions; Decision; Transport;

The interaction between tolls and capacity investment in serial and parallel transport networks

The purpose of this paper is to compare the interaction between pricing and capacity decisions on simple serial and parallel transport networks. When individual links of the network are operated by different regional or national authorities, toll and capacity competition is likely to result. Moreover, the problem is potentially complicated by the presence of both local and transit demand on each link of the network. We bring together and extend the recent literature on the topic and, using both theory and numerical simulation techniques, provide a careful comparison of toll and capacity interaction on serial and parallel network structures. First, we show that there is more tax exporting in serial transport corridors than on competing parallel road networks. Second, the inability to toll transit has quite dramatic negative welfare effects on parallel networks. On the contrary, in serial transport corridors it may actually be undesirable to allow the tolling of transit at all. Third, if the links are exclusively used by transit transport, toll and capacity decisions are independent in serial networks. This does not generally hold in the presence of local transport. Moreover, it contrasts with a parallel setting where regional authorities compete for transit; in that case, regional investment in capacity leads to lower Nash equilibrium tolls.congestion pricing, transport investment, transit traffic

The interaction between tolls and capacity investment in serial and parallel transport networks.

The purpose of this paper is to compare the interaction between pricing and capacity decisions on simple serial and parallel transport networks. When individual links of the network are operated by different regional or national authorities, toll and capacity competition is likely to result. Moreover, the problem is potentially complicated by the presence of both local and transit demand on each link of the network. We bring together and extend the recent literature on the topic and, using both theory and numerical simulation techniques, provide a careful comparison of toll and capacity interaction on serial and parallel network structures. First, we show that there is more tax exporting in serial transport corridors than on competing parallel road networks. Second, the inability to toll transit has quite dramatic negative welfare effects on parallel networks. On the contrary, in serial transport corridors it may actually be undesirable to allow the tolling of transit at all. Third, if the links are exclusively used by transit transport, toll and capacity decisions are independent in serial networks. This does not generally hold in the presence of local transport. Moreover, it contrasts with a parallel setting where regional authorities compete for transit; in that case, regional investment in capacity leads to lower Nash equilibrium tolls.Congestion pricing; Transport investment; Transit traffic;