Toll competition in highway transportation networks

Within a highway transportation network, the social welfare implications of two different groups of agents setting tolls in competition for revenues are studied. The first group comprises private sector toll road operators aiming to maximise revenues. The second group comprises local governments or jurisdictions who may engage in tax exporting. Extending insights from the public economics literature, jurisdictions tax export because when setting tolls to maximise welfare for their electorate, they simultaneously benefit from revenues from extra-jurisdictional users. Hence the tolls levied by both groups will be higher than those intended solely to internalise congestion, which then results in welfare losses. Therefore the overarching question investigated is the extent of welfare losses stemming from such competition for toll revenues. While these groups of agents are separately studied, the interactions between agents in each group in competition can be modelled within the common framework of Equilibrium Problems with Equilibrium Constraints. Several solution algorithms, adapting methodologies from microeconomics as well as evolutionary computation, are proposed to identify Nash Equilibrium toll levels. These are demonstrated on realistic transportation networks. As an alternative paradigm to competition, the possibilities for co-operation between agents in each group are also explored. In the case of toll road operators, the welfare consequences of competition could be positive or adverse depending on the interrelationships between the toll roads in competition. The results therefore generalise those previously obtained to a more realistic setting investigated here. In the case of competition between jurisdictions, it is shown that the fiscal externality of tax exporting resulting from their toll setting decisions can substantially reduce the welfare gains from internalising congestion. The ability of regulation, co-operation and bilateral bargaining to reduce the welfare losses are assessed. The research thus contributes to informing debates regarding the appropriate level of institutional governance for toll pricing policies

Invasive Species in Forests and Rangelands of the United States

This open access book describes the serious threat of invasive species to native ecosystems. Invasive species have caused and will continue to cause enormous ecological and economic damage with ever increasing world trade. This multi-disciplinary book, written by over 100 national experts, presents the latest research on a wide range of natural science and social science fields that explore the ecology, impacts, and practical tools for management of invasive species. It covers species of all taxonomic groups from insects and pathogens, to plants, vertebrates, and aquatic organisms that impact a diversity of habitats in forests, rangelands and grasslands of the United States. It is well-illustrated, provides summaries of the most important invasive species and issues impacting all regions of the country, and includes a comprehensive primary reference list for each topic. This scientific synthesis provides the cultural, economic, scientific and social context for addressing environmental challenges posed by invasive species and will be a valuable resource for scholars, policy makers, natural resource managers and practitioners

Decolonizing Science in Latin American Art

Projects that bring the ‘hard’ sciences into art are increasingly being exhibited in galleries and museums across the world. In a surge of publications on the subject, few focus on regions beyond Europe and the Anglophone world. Decolonizing Science in Latin American Art assembles a new corpus of art-science projects by Latin American artists, ranging from big-budget collaborations with NASA and MIT to homegrown experiments in artists’ kitchens. While they draw on recent scientific research, these art projects also ‘decolonize’ science. If increasing knowledge of the natural world has often gone hand-in-hand with our objectification and exploitation of it, the artists studied here emphasize the subjectivity and intelligence of other species, staging new forms of collaboration and co-creativity beyond the human. They design technologies that work with organic processes to promote the health of ecosystems, and seek alternatives to the logics of extractivism and monoculture farming that have caused extensive ecological damage in Latin America. They develop do-it-yourself, open-source, commons-based practices for sharing creative and intellectual property. They establish critical dialogues between Western science and indigenous thought, reconnecting a disembedded, abstracted form of knowledge with the cultural, social, spiritual, and ethical spheres of experience from which it has often been excluded. Decolonizing Science in Latin American Art interrogates how artistic practices may communicate, extend, supplement, and challenge scientific ideas. At the same time, it explores broader questions in the field of art, including the relationship between knowledge, care, and curation; nonhuman agency; art and utility; and changing approaches to participation. It also highlights important contributions by Latin American thinkers to themes of global significance, including the Anthropocene, climate change, and environmental justice. ‘Joanna Page presents a deeply researched account of contemporary art-science projects in Latin America. She situates them at the crux of current discussions on the decolonization of both the sciences and the arts: by questioning Eurocentric views on humanism and modernity, exploring expanded ideas of perception and cognition, and placing Western scientific knowledge within constellations of beliefs and practices that have been marginalised by colonial histories.’ – Mara Polgovsky Ezcurra, Birkbeck Colleg