Apprenticeship and Conservation Incentives

Apprentice programs offer a method to encourage responsible individual behavior by laying the foundation for successful collective property rights. Apprenticeship has three purposes: to restrict the rate of entry, to affect the quality of the participant, and to create the conditions for collective action for sustainability. Apprenticeship could be an important fishery management tool, particularly in decentralized, adaptive management regimes that require ongoing, multi-party negotiation for success. It is not vocational training; instead it serves a public purpose: to create the conditions for stewardship and participation in management. This perception of collective property right mimics customary practice in some successful traditional fisheries such as the Maine lobster fishery where customary practice has been demonstrated both to have conservation benefits and to lower enforcement costs. Case information from Maine’s new, statutory lobster apprentice program is discussed. Apprenticeship creates conditions for responsible behavior by creating a stable population that can develop long term assurances about expected behavior and can develop credible internal monitoring and sanctions. In addition to requiring a personal investment of time, it provides information about fishing ethics and non-fishing information about basic biology, ecology, and participation in the management system. This, because it changes the frame of reference, should affect individual behavior both fishing and as participants in management. Apprenticeship focuses on the individual fishing as the principal actor in conservation. The apprenticeship approach bolsters both co-management and, for that matter, conventional limited entry programs as well

Fluctuation-dissipation relation and the Edwards entropy for a glassy granular compaction model

We analytically study a one dimensional compaction model in the glassy regime. Both correlation and response functions are calculated exactly in the evolving dense and low tapping strength limit, where the density relaxes in a $1/\ln t$ fashion. The response and correlation functions turn out to be connected through a non-equilibrium generalisation of the fluctuation-dissipation theorem. The initial response in the average density to an increase in the tapping strength is shown to be negative, while on longer timescales it is shown to be positive. On short time scales the fluctuation-dissipation theorem governs the relation between correlation and response, and we show that such a relationship also exists for the slow degrees of freedom, albeit with a different temperature. The model is further studied within the statistical theory proposed by Edwards and co-workers, and the Edwards entropy is calculated in the large system limit. The fluctuations described by this approach turn out to match the fluctuations as calculated through the dynamical consideration. We believe this to be the first time these ideas have been analytically confirmed in a non-mean-field model.Comment: 4 pages, 3 figure

Trading Off Tax Distortion and Tax Evasion

Tax evasion is modeled as a risky activity and integrated into a standard problem of optimal tax design. It is shown that there is a trade off between reducing tax evasion and reducing tax distortion. Thus it is efficient to supplement a broad-based wage tax by a tax on specific consumption if the former is evaded and the latter not. The optimal tax structure can be characterized by an explicit formula.Tax evasion, risk-taking, optimal taxation

There is no finite-variable equational axiomatization of representable relation algebras over weakly representable relation algebras

We prove that any equational basis that defines RRA over wRRA must contain infinitely many variables. The proof uses a construction of arbitrarily large finite weakly representable but not representable relation algebras whose "small" subalgebras are representable.Comment: To appear in Review of Symbolic Logi

Functorial properties of Putnam's homology theory for Smale spaces

We investigate functorial properties of Putnam's homology theory for Smale spaces. Our analysis shows that the addition of a conjugacy condition is necessary to ensure functoriality. Several examples are discussed that elucidate the need for our additional hypotheses. Our second main result is a natural generalization of Putnam's Pullback Lemma from shifts of finite type to non-wandering Smale spaces.Comment: Updated to agree with published versio

Phase gate and readout with an atom/molecule hybrid platform

We suggest a combined atomic/molecular system for quantum computation, which takes advantage of highly developed techniques to control atoms and recent experimental progress in manipulation of ultracold molecules. We show that two atoms of different species in a given site, {\it e.g.}, in an optical lattice, could be used for qubit encoding, initialization and readout, with one atom carrying the qubit, the other enabling a gate. In particular, we describe how a two-qubit phase gate can be realized by transferring a pair of atoms into the ground rovibrational state of a polar molecule with a large dipole moment, and allowing two molecules to interact via their dipole-dipole interaction. We also discuss how the reverse process of coherently transferring a molecule into a pair of atoms could be used as a readout tool for molecular quantum computers

Food habits of Steller sea lions (Eumetopias jubatus) off Oregon and northern California, 1986–2007

We described the diet of the eastern stock of Steller sea lions (Eumetopias jubatus) from 1416 scat samples collected from five sites in Oregon and northern California from 1986 through 2007. A total of 47 prey types from 30 families were identified. The most common prey was Pacific hake (Merluccius productus), followed by salmonids (Oncorhynchus spp.), skates (Rajidae), Pacific lamprey (Lampetra tridentata), herrings (Clupeidae), rockfish (Sebastes spp.), and northern anchovy (Engraulis mordax). Steller sea lion diet composition varied seasonally, annually, and spatially. Hake and salmonids were the most commonly identified prey in scats collected during the summer (breeding season), whereas hake and skate were most common in the nonbreeding season. Continued research on Steller sea lion diet and foraging behavior in the southern extent of their range is necessary to address issues such as climate change, interaction with competing California sea lions, and predation impacts on valuable or sensitive fish stocks