10,849 research outputs found
Declining Commodity Program Payments and Enhanced Environmental Regulations: Impacts on Acreage Allocation in the Great Plains
Environmental Economics and Policy,
Spin chain in magnetic field: limitations of the large-N mean-field theory
Motivated by the recent success in describing the spin and orbital spectrum
of a spin-orbital chain using a large-N mean-field approximation [Phys. Rev. B
91, 165102 (2015)], we apply the same formalism to the case of a spin chain in
the external magnetic field. It occurs that in this case, which corresponds to
N=2 in the approximation, the large-N mean-field theory cannot qualitatively
reproduce the spin excitation spectra at high magnetic fields, which polarize
more than 50% of the spins in the magnetic ground state. This, rather
counterintuitively, shows that the physics of a spin chain can under some
circumstances be regarded as more complex than the physics of a spin-orbital
chain.Comment: 4 pages, 3 figures; appeared in the proceedings of the European
Conference "Physics of Magnetism" (2014
WELFARE EFFECTS OF FISHERY POLICIES: NATIVE AMERICAN TREATY RIGHTS AND RECREATIONAL SALMON FISHING
Severe declines in Pacific Northwest salmon stocks, coupled with increasing recreational demands, and judicial decisions supporting Native American fishing rights create challenges for fishery agencies. This article explores the welfare effects on recreational anglers of alternative salmon allocation policies to meet Native American treaty rights. A discrete choice random utility model, coupled with a Poisson trip frequency model, is used to analyze these welfare effects. The model is fit to survey data from the Willamette River spring chinook fishery, an important recreational fishery in Oregon. Management options have dramatically different welfare effects.Resource /Energy Economics and Policy,
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