Strategic Trade Policy with Polynomial Costs

 We investigate how the superiority of the optimal subsidy or tariff in an international Cournot oligopoly depends on the production technology used in the industry, an interesting issue that has not been analyzed in the literature. We establish that the welfare superiority of the optimal subsidy or tariff depends on the relative steepness of the firms' common marginal cost curve: when it is relatively steep, tariffs are superior to subsidies in enhancing domestic welfare, and vice versa. When both instruments are used simultaneously, the tariff component becomes more important as the marginal cost curve steepens.

Relic density and CMB constraints on dark matter annihilation with Sommerfeld enhancement

We calculate how the relic density of dark matter particles is altered when their annihilation is enhanced by the Sommerfeld mechanism due to a Yukawa interaction between the annihilating particles. Maintaining a dark matter abundance consistent with current observational bounds requires the normalization of the s-wave annihilation cross section to be decreased compared to a model without enhancement. The level of suppression depends on the specific parameters of the particle model, with the kinetic decoupling temperature having the most effect. We find that the cross section can be reduced by as much as an order of magnitude for extreme cases. We also compute the mu-type distortion of the CMB energy spectrum caused by energy injection from such Sommerfeld-enhanced annihilation. Our results indicate that in the vicinity of resonances, associated with bound states, distortions can be large enough to be excluded by the upper limit |mu|<9.0x10^(-5) found by the COBE/FIRAS experiment.Comment: 10 pages, 6 figures, accepted for publication in Physical Review D. Corrections to eqs. 9,10,14 and 16. Figures updated accordingly. No major changes to previous results. Website with online tools for Sommerfeld-related calculations can be found at http://www.mpa-garching.mpg.de/~vogelsma/sommerfeld

Probing small xx parton densities in ultraperipheral AAAA and pApA collisions at the LHC

We calculate production rates for several hard processes in ultraperipheral proton-nucleus and nucleus-nucleus collisions at the LHC. The resulting high rates demonstrate that some key directions in small $x$ research proposed for HERA will be accessible at the LHC through these ultraperipheral processes. Indeed, these measurements can extend the HERA $x$ range by roughly a factor of 10 for similar virtualities. Nonlinear effects on the parton densities will thus be significantly more important in these collisions than at HERA.Comment: Submitted to Phys. Rev. Lett., 4 pages, 5 figure

Government policy should be based on respect and responsiveness rather than statistics

There are significant problems with statistics-based policy, argues Mark D. White. He writes that governments should eschew the use of output or well-being statistics and instead focus on respect and responsiveness. This would mean encouraging the ability and right of individuals to make choices in their own interests and responding to the needs and concerns of the people as expressed by the people

Basing government policy on happiness or well-being is misguided

Regardless of the motivation and intention behind it, the move to base government policy on measures of happiness is fraught with problems at every level, argues Mark D. White. Reorienting policy towards happiness suffers from problems of definition, measurement, and implementation

Book review: valuing life: humanizing the regulatory state by Cass Sunstein

In Valuing Life, Cass Sunstein surveys a wide range of practical research and real-life policymaking in his characteristically lucid style, offering a candid and humble account of his administrative tenure in Washington. He performs an invaluable service in revealing how government regulators balance pragmatic concerns of resource scarcity with principled ideals of respect and dignity, writes Mark D. White

On the Relationship between Economics and Ethics

Economics and ethics have been linked since the days of Adam Smith, but this connection became tenuous after the formalization of economic theory in the twentieth century, the success of which in academia, government, and business serves to insulate it from ethical critique. Nonetheless, a field of “economics and ethics” has developed to restore this connection, albeit in two directions with disparate methodological approaches: one applying mainstream economic theory, primarily based in utilitarian ethics, to topics of ethical concern, and the other incorporating alternate forms of ethics, such as deontology and virtue ethics, to enrich economic analysis

Introduction to The Oxford Handbook of Ethics and Economics

Economics and ethics are both valuable tools for analyzing the behavior and actions of human beings and institutions. Adam Smith, the father of modern economics, considered them two sides of the same coin, but since economics was formalized and mathematicised in the late 1800s and early 1900s, the fields have largely followed separate paths. The Oxford Handbook of Ethics and Economics provides a timely and thorough survey of the various ways ethics can, does, and should inform economic theory and practice. The first part of the book, Foundations, explores how the most prominent schools of moral philosophy relate to economics; asks how morals relevant to economic behavior may have evolved; and explains how various approaches to economics incorporate ethics into their work. The second part, Applications, looks at the ethics of commerce, finance, and markets; uncovers the moral dilemmas involved with making decisions regarding social welfare, risk, and harm to others; and explores how ethics is relevant to major topics within economics, such as health care and the environment. With esteemed contributors from economics and philosophy, The Oxford Handbook of Ethics and Economics is a resource for scholars in both disciplines and those in related fields. It highlights the close relationship between ethics and economics in the past while and lays a foundation for further integration going forward

Web matrices : structural properties and generating combinatorial identities

In this paper we present new results for the combinatorics of web diagrams and web worlds. These are discrete objects that arise in the physics of calculating scattering amplitudes in non-abelian gauge theories. Web-colouring and web-mixing matrices (collectively known as web matrices) are indexed by ordered pairs of web-diagrams and contain information relating the number of colourings of the first web diagram that will produce the second diagram. We introduce the black diamond product on power series and show how it determines the web-colouring matrix of disjoint web worlds. Furthermore, we show that combining known physical results with the black diamond product gives a new technique for generating combinatorial identities. Due to the complicated action of the product on power series, the resulting identities appear highly non-trivial. We present two results to explain repeated entries that appear in the web matrices. The first of these shows how diagonal web matrix entries will be the same if the comparability graphs of their associated decomposition posets are the same. The second result concerns general repeated entries in conjunction with a flipping operation on web diagrams. We present a combinatorial proof of idempotency of the web-mixing matrices, previously established using physical arguments only. We also show how the entries of the square of the web-colouring matrix can be achieved by a linear transformation that maps the standard basis for formal power series in one variable to a sequence of polynomials. We look at one parameterized web world that is related to indecomposable permutations and show how determining the web-colouring matrix entries in this case is equivalent to a combinatorics on words problem