13,105 research outputs found
Measuring Taxes on Income from Capital: Evidence from the UK
This paper explores the empirical properties of alternative measures of the taxation of income from capital, using UK data over the last thirty years. We analyse measures of effective marginal and average tax rates, based on applying the legal parameters of the tax system to a hypothetical investment; and also measures based on observed tax payments or liabilities, scaled by various measures of income. There is a significant difference between these measures, both in their level and in how they move over time. The implicit assumption in some empirical work that these measures are broadly comparable to each other is not justified.
Phenomenology of the CAH+ measure
The CAH+ measure regulates the infinite spacetime volume of the multiverse by
constructing a surface of constant comoving apparent horizon (CAH) and then
removing the future lightcones of all points on that surface (the latter
prescription is referred to by the "+" in the name of the measure). This
measure was motivated by the conjectured duality between the bulk of the
multiverse and its future infinity and by the causality condition, requiring
that the cutoff surfaces of the measure should be spacelike or null. Here we
investigate the phenomenology of the CAH+ measure and find that it does not
suffer from any known pathologies. The distribution for the cosmological
constant Lambda derived from this measure is in a good agreement with the
observed value, and the distribution for the number of inflationary e-foldings
satisfies the observational constraint. The CAH+ measure does not exhibit any
"runaway" behaviors at zero or negative values of Lambda, which have been
recently shown to afflict a number of other measures.Comment: 35 pages, including 6 figures and 2 appendices; v2 corrections in
Section 2.4, conclusions unchange
How to take the interstellar weather with you in pulsar timing analysis
Here we present a Bayesian method of including discrete measurements of
dispersion measure due to the interstellar medium in the direction of a pulsar
as prior information in the analysis of that pulsar. We use a simple simulation
to show the efficacy of this method, where the inclusion of the additional
measurements results in both a significant increase in the precision with which
the timing model parameters can be obtained, and an improved upper limit on the
amplitude of any red noise in the dataset. We show that this method can be
applied where no multi-frequency data exists across much of the dataset, and
where there is no simultaneous multi-frequency data for any given observing
epoch. Including such information in the analysis of upcoming International
Pulsar Timing Array (IPTA) and European Pulsar Timing Array (EPTA) data
releases could therefore prove invaluable in obtaining the most constraining
limits on gravitational wave signals within those datasets.Comment: 7 pages, 1 Table, 3 Figures. arXiv admin note: substantial text
overlap with arXiv:1310.212
Mathematical programs with equilibrium constraints: automatic reformulation and solution via constrained optimization
Constrained optimization has been extensively used to solve many large scale deterministic problems arising in economics, including, for example, square systems of equations and nonlinear programs. A separate set of models have been generated more recently, using complementarity to model various phenomenon, particularly in general equilibria. The unifying framework of mathematical programs with equilibrium constraints (MPEC) has been postulated for problems that combine facets of optimization and complementarity. This paper briefly reviews some methods available to solve these problems and described a new suite of tools for working with MPEC models. Computational results demonstrating the potential of this tool are given that automatically construct and solve a variety of different nonlinear programming reformulations of MPEC problems.\ud
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This material is based on research partially supported by the National Science Foundation Grant CCR-9972372, the Air Force Office of Scientific Research Grant F49620-01-1-0040, Microsoft Corporation and the Guggenheim Foundation
Vagus nerve stimulation paired with tactile training improved sensory function in a chronic stroke patient
Background: Recent studies indicate that vagus nerve stimulation (VNS) paired with rehabilitation can enhance neural plasticity in the primary sensory and motor cortices, improve forelimb function after stroke in animal models and improve motor function in patients with arm weakness after stroke. OBJECTIVE:To gain âfirst-in-manâ experience of VNS paired with tactile training in a patient with severe sensory impairment after stroke. Methods: During the long-term follow-up phase of a clinical trial of VNS paired with motor rehabilitation, a 71-year-old man who had made good motor recovery had ongoing severe sensory loss in his left hand and arm. He received VNS paired with tactile therapy in an attempt to improve his sensory function. During twenty 2-hour sessions, each passive and active tactile event was paired with a 0.5 second burst of 0.8âmA VNS. Sensory function was measured before, halfway through, and after this therapy. Results: The patient did not report any side effects during or following VNS+Tactile therapy. Quantitative measures revealed lasting and clinically meaningful improvements in tactile threshold, proprioception, and stereognosis. After VNS+Tactile therapy, the patient was able to detect tactile stimulation to his affected hand that was eight times less intense, identify the joint position of his fingers in the affected hand three times more often, and identify everyday objects using his affected hand seven times more often, compared to baseline. Conclusions: Sensory function significantly improved in this man following VNS paired with tactile stimulation. This approach merits further study in controlled clinical trials
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