45,257 research outputs found

    The Dummies Guide' to Lottery Design.

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    This paper outlines the issues relevant to the operation of lottery games. We consider how such games should be designed, what a portfolio of games might look like, how the operator should be regulated, how spending on lottery games should be taxed, and what considerations are relevant to the use of the revenue from such games.LOTTERY ; GAMES ; MONEY ; TAXATION

    Using Rasch analysis to form plausible health states amenable to valuation: the development of CORE-6D from CORE-OM in order to elicit preferences for common mental health problems

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    Purpose: To describe a new approach for deriving a preference-based index from a condition specific measure that uses Rasch analysis to develop health states. Methods: CORE-OM is a 34-item instrument monitoring clinical outcomes of people with common mental health problems. CORE-OM is characterised by high correlation across its domains. Rasch analysis was used to reduce the number of items and response levels in order to produce a set of unidimensionally-behaving items, and to generate a credible set of health states corresponding to different levels of symptom severity using the Rasch item threshold map. Results: The proposed methodology resulted in the development of CORE-6D, a 2-dimensional health state description system consisting of a unidimensionally-behaving 5-item emotional component and a physical symptom item. Inspection of the Rasch item threshold map of the emotional component helped identify a set of 11 plausible health states, which, combined with the physical symptom item levels, will be used for the valuation of the instrument, resulting in the development of a preference-based index. Conclusions: This is a useful new approach to develop preference-based measures where the domains of a measure are characterised by high correlation. The CORE-6D preference-based index will enable calculation of Quality Adjusted Life Years in people with common mental health problems

    Drag coefficients for partially inflated flat circular parachutes

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    Free-body tests of flat circular parachutes and determination of aerodynamic drag coefficients during partial inflatio

    Angle Dependence of Landau Level Spectrum in Twisted Bilayer Graphene

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    In the context of the low energy effective theory, the exact Landau level spectrum of quasiparticles in twisted bilayer graphene with small twist angle is analytically obtained by spheroidal eigenvalues. We analyze the dependence of the Landau levels on the twist angle to find the points, where the two-fold degeneracy for twist angles is lifted in the nonzero modes and below/above which massive/massless fermion pictures become valid. In the perpendicular magnetic field of 10\,T, the degeneracy is removed at θdeg∼3∘\theta_{{\rm deg}}\sim 3^\circ %angles around 3 degrees for a few low levels, specifically, θdeg≃2.56∘\theta_{\rm deg}\simeq 2.56^\circ for the first pair of nonzero levels and θdeg≃3.50∘\theta_{\rm deg}\simeq 3.50^\circ for the next pair. Massive quasiparticle appears at θ<θc≃1.17∘\theta<\theta_{{\rm c}}\simeq 1.17^\circ in 10\,T, %angles less than 1.17 degrees. which match perfectly with the recent experimental results. Since our analysis is applicable to the cases of arbitrary constant magnetic fields, we make predictions for the same experiment performed in arbitrary constant magnetic fields, e.g., for B=40\,T we get θc≃2.34∘\theta_{\rm c}\simeq 2.34^\circ and the sequence of angles θdeg=5.11,7.01,8.42,...\theta_{\rm deg} = 5.11, 7.01, 8.42,... for the pairs of nonzero energy levels. The symmetry restoration mechanism behind the massive/massless transition is conjectured to be a tunneling (instanton) in momentum space.Comment: 8 pages, 7 figures, version to appear in PR
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