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    Multi-Attribute Choice Modeling of Australia’s Rivers and Wetlands: A Meta-Analysis of Ten Years of Research

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    A meta-analysis is presented of the empirical findings of 10 years of choice experiment applications to water and wetland management issues in Australia. A random effects Tobit model is estimated to investigate the suitability of using existing willingness to pay (WTP) values derived from estimated choice models for the purpose of benefits transfer. The random effects model outperforms the fixed effects model in terms of predictive power. An analysis of variance reveals that the survey method, sample size, and statistical model are important determinants of estimation precision and error. The use of different attributes, measurement units and levels in choice experiments makes it hard to compare WTP values for environmental attributes from different studies. The benefits associated with current and possible future use of the water resources are valued significantly higher than the nonuse benefits. Except for the systematically lower values for the Fitzroy, WTP values are more or less transferable across catchments. Other important control variables when transferring the results from choice models across water and wetland policy contexts include income levels of the population of beneficiaries and methodological study characteristics such as the number of choice tasks in the choice experiment.choice experiments, stated preferences, value transfer, validity

    Dynamics in crop protection, agriculture and the food chain in Europe

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    Overview on the vital role of plant protection in Europe in maintaining and enhancing the dynamics of agricultural production and the food chain. The report offers an overview of the achievements of more sustainable production methods in European agriculture, and the actions taken by the farming community in response to private market initiatives and public policies. Such actions establish new farming systems. The report offers factual information, as well as analyses to put trends in context

    The chiral symplectic universality class

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    We report a numerical investigation of localization in the SU(2) model without diagonal disorder. At the band center, chiral symmetry plays an important role. Our results indicate that states at the band center are critical. States away from the band center but not too close to the edge of the spectrum are metallic as expected for Hamiltonians with symplectic symmetry.Comment: accepted in Proceedings of Localisation 2002 Conference, Tokyo, Japan (to be published as supplement of J. Phys. Soc. Japan

    Bott periodicity for the topological classification of gapped states of matter with reflection symmetry

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    Using a dimensional reduction scheme based on scattering theory, we show that the classification tables for topological insulators and superconductors with reflection symmetry can be organized in two period-two and four period-eight cycles, similar to the Bott periodicity found for topological insulators and superconductors without spatial symmetries. With the help of the dimensional reduction scheme the classification in arbitrary dimensions d1d \ge 1 can be obtained from the classification in one dimension, for which we present a derivation based on relative homotopy groups and exact sequences to classify one-dimensional insulators and superconductors with reflection symmetry. The resulting classification is fully consistent with a comprehensive classification obtained recently by Shiozaki and Sato [Phys.\ Rev.\ B {\bf 90}, 165114 (2014)]. The use of a scattering-matrix inspired method allows us to address the second descendant \bZ_2 phase, for which the topological nontrivial phase was previously reported to be vulnerable to perturbations that break translation symmetry.Comment: 18 pages, 7 figure

    Why not be a desertist?: Three arguments for desert and against luck egalitarianism

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    Many philosophers believe that luck egalitarianism captures “desert-like” intuitions about justice. Some even think that luck egalitariansm distributes goods in accordance with desert. In this paper, we argue that this is wrong. Desertism conflicts with luck egalitarianism in three important contexts, and, in these contexts, desertism renders the proper moral judgment. First, compared to desertism, luck egalitarianism is sometimes too stingy: it fails to justly compensate people for their socially valuable contributions—when those contributions arose from “option luck”. Second, luck egalitarianism is sometimes too restrictive: it fails to justly compensate people who make a social contribution when that contribution arose from “brute luck”. Third, luck egalitarianism is too limited in scope: it cannot diagnose economic injustice arising independently of comparative levels of justice. The lesson of this paper is that luck egalitarians should consider supplementing their theory with desert considerations. Or, even better, consider desertism as a superior alternative to their theory

    Pumped current and voltage for an adiabatic quantum pump

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    We consider adiabatic pumping of electrons through a quantum dot. There are two ways to operate the pump: to create a dc current Iˉ{\bar I} or to create a dc voltage Vˉ{\bar V}. We demonstrate that, for very slow pumping, Iˉ{\bar I} and Vˉ{\bar V} are not simply related via the dc conductance GG as Iˉ=VˉG\bar I = \bar V G. For the case of a chaotic quantum dot, we consider the statistical distribution of VˉGIˉ{\bar V} G - {\bar I}. Results are presented for the limiting cases of a dot with single channel and with multichannel point contacts.Comment: 6 pages, 4 figure

    Residential Mobility of Older Adults in the Dutch Housing Market: Do Individual Characteristics and Housing Attributes Have an Effect on Mobility?

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    The ageing of the population will change many societies in unprecedented ways. The changing age composition does not only create a burden on existing income systems and health care systems, but also affects the geographical mobility of populations. The objective of this paper is to provide some first insights into the moving behaviour of older adults in the Netherlands. By using data of the Housing Research Netherlands (HRN) 2009 survey, it was possible to investigate whether or not later-life residential mobility is influenced by individual characteristics and housing attributes. The responses of migrants and non-migrants are compared by conducting several two-way-chi-square analyses. The results of these descriptive analyses demonstrate that migrants indeed differ from non-migrants and that these differences are mostly related to housing attributes

    Semiclassical theory of speckle correlations

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    Coherent wave propagation in random media results in a characteristic speckle pattern, with spatial intensity correlations with short-range and long-range behavior. Here, we show how the speckle correlation function can be obtained from a ray picture for two representative geometries: A chaotic cavity and a random waveguide. Our calculation allows us to study the crossover between a "ray limit" and a "wave limit", in which the Ehrenfest time τE\tau_E is larger or smaller than the typical transmission time τD\tau_D, respectively. Remarkably, long-range speckle correlations persist in the ray limit τEτD\tau_E \gg \tau_D.Comment: 13 pages, 7 figure
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