36,238 research outputs found
Why Do Companies Pay Dividends?
This paper presents a simple model of market equilibrium to explain why firms that maximize the value of their shares pay dividends even though the funds could instead be retained and subsequently distributed to shareholders in a way that would allow them to be taxed more favorably as capital gains. The two principal ingredients of our explanation are:(1) the conflicting preferences of shareholders in different tax brackets and (2) the shareholders' desire for portfolio diversification, we show that companies will pay a positive fraction of earnings in dividends. We also provide some comparative static analysis of dividend behavior with respect to tax parameters and to the conditions determining the riskiness of the securities.
On quasi-heredity and cell module homomorphisms in the symplectic blob algebra
This paper reports key advances in the study of the representation theory of
the symplectic blob algebra. For suitable specialisations of the parameters we
construct four large families of homomorphisms between cell modules. We hence
find a large family of non-semisimple specialisations. We find a minimal poset
(i.e. least number of relations) for the symplectic blob as a quasi-hereditary
algebra.Comment: 45 pages. arXiv admin note: text overlap with arXiv:0807.410
The marine ΔR For Nenumbo (Solomon Islands): A case study in calculating reservoir offsets form paired sample data
It is necessary to calculate location-specific marine ΔR values in order to calibrate marine samples using calibration curves such as those provided through the IntCal98 (Stuiver et al. 1998) data. Where known-age samples are available, this calculation is straightforward (i.e. Stuiver et al. 1986). In the case that a paired marine/terrestrial sample calculation is performed, however, the standard calculation (i.e. Stuiver and Braziunas 1993) requires that the samples are treated as relating to isochronous events. This may not be an appropriate assumption for many archaeological paired samples. In this paper, we present an approach to calculating marine ΔR values that does not require the dated events to be treated as isochronous. When archaeological evidence allows the dated events to be tightly temporally constrained, the approach presented here and that described by Stuiver and Braziunas (1993) give very similar results. However, where tight temporal constraints are less certain, the 2 approaches can give rise to differing results. The example analysis considered here shows that a ΔR of –81 ± 64 ¹⁴C yr is appropriate for samples in the vicinity of Nenumbo (Reef Islands, southeast Solomon Islands) around the period 2000–3000 BP
Quantum Gravity and Higher Curvature Actions
Effective equations are often useful to extract physical information from
quantum theories without having to face all technical and conceptual
difficulties. One can then describe aspects of the quantum system by equations
of classical type, which correct the classical equations by modified
coefficients and higher derivative terms. In gravity, for instance, one expects
terms with higher powers of curvature. Such higher derivative formulations are
discussed here with an emphasis on the role of degrees of freedom and on
differences between Lagrangian and Hamiltonian treatments. A general scheme is
then provided which allows one to compute effective equations perturbatively in
a Hamiltonian formalism. Here, one can expand effective equations around any
quantum state and not just a perturbative vacuum. This is particularly useful
in situations of quantum gravity or cosmology where perturbations only around
vacuum states would be too restrictive. The discussion also demonstrates the
number of free parameters expected in effective equations, used to determine
the physical situation being approximated, as well as the role of classical
symmetries such as Lorentz transformation properties in effective equations. An
appendix collects information on effective correction terms expected from loop
quantum gravity and string theory.Comment: 28 pages, based on a lecture course at the 42nd Karpacz Winter School
of Theoretical Physics ``Current Mathematical Topics in Gravitation and
Cosmology,'' Ladek, Poland, February 6-11, 200
Extraction of black hole coalescence waveforms from noisy data
We describe an independent analysis of LIGO data for black hole coalescence
events. Gravitational wave strain waveforms are extracted directly from the
data using a filtering method that exploits the observed or expected
time-dependent frequency content. Statistical analysis of residual noise, after
filtering out spectral peaks (and considering finite bandwidth), shows no
evidence of non-Gaussian behaviour. There is also no evidence of anomalous
causal correlation between noise signals at the Hanford and Livingston sites.
The extracted waveforms are consistent with black hole coalescence template
waveforms provided by LIGO. Simulated events, with known signals injected into
real noise, are used to determine uncertainties due to residual noise and
demonstrate that our results are unbiased. Conceptual and numerical differences
between our RMS signal-to-noise ratios (SNRs) and the published matched-filter
detection SNRs are discussed.Comment: 15 pages, 11 figures. Version accepted for publicatio
Welfare Reform in Agricultural California
When welfare reforms were enacted in 1996, a higher than average percentage of residents in the agricultural heartland of California, the San Joaquin Valley, received cash assistance. Average annual unemployment rates during the 1990s ranged from 12% to 20%, and 15% to 20% of residents in major farming counties received cash benefits. This analysis develops and estimates a two-equation cross-sectionally correlated and timewise autoregressive model to test the hypothesis that in agricultural areas, seasonal work, low earnings, and high unemployment, as well as few entry-level jobs that offer wages and benefits equivalent to welfare benefits, promote welfare use and limit the potential of local labor markets to absorb ex-welfare recipients.cross-sectionally correlated and timewise autoregressive model, farm workers, immigration, welfare reform, Public Economics,
Instantons of Type IIB Supergravity in Ten Dimensions
A family of SO(10) symmetric instanton solutions in Type IIB supergravity is
developed. The instanton of least action is a candidate for the low-energy,
semiclassical approximation to the {D=--1} brane. Unlike a previously published
solution,[GGP] this admits an interpretation as a tunneling amplitude between
perturbatively degenerate asymptotic states, but with action twice that found
previously. A number of associated issues are discussed such as the relation
between the magnetic and electric pictures, an inversion symmetry of the
dilaton and the metric, the topology of the background, and some
properties of the solution in an "instanton frame" corresponding to a
Lagrangian in which the dilaton's kinetic energy vanishes.Comment: 15 pages, no figures; Version 2 has revised sections IV and V.
Earlier equations are essentially unchanged, but interpretation changed, on
advice of counse
- …
