5,291 research outputs found
How did the 2003 dividend tax cut affect stock prices?
We test the hypothesis that the 2003 dividend tax cut boosted U.S. stock prices and thus lowered the cost of equity. Using an event- study methodology, we attempt to identify an aggregate stock market effect by comparing the behavior of U.S. common stock prices to that of European stocks and real estate investment trusts. We also examine the relative cross-sectional response of prices on high-dividend versus low-dividend paying stocks. We do not find any imprint of the dividend tax cut news on the value of the aggregate U.S. stock market. On the other hand, high-dividend stocks outperformed low-dividend stocks by a few percentage points over the event windows, suggesting that the tax cut did induce asset reallocation within equity portfolios. Finally, the positive abnormal returns on non-dividend paying U.S. stocks in 2003 do not appear to be tied to tax-cut news.Taxation ; Stock - Prices
Wait, Who are we Talking About Here? Searching for a Consistent Approach to Applying RFRA to Corporations
There is perhaps no idea in contemporary American law that is more publicly contentious than that of “corporate personhood.” Of all of the Supreme Court cases dealing with corporations and the corporate entity, few probably thought that a decision could surpass Citizens United in public controversy and divisiveness produced by the decision, which brought the legal fiction of the “corporate person” to the forefront of popular debate and discussion. Then came Burwell v. Hobby Lobby Stores, Inc., which not only addressed whether corporations could “act” in a manner that seemed only a possibility for “real” or “natural” persons, which recalled the contentious question in Citizens United, but did so in the context of religious liberty and women’s repro-ductive rights, both of which tend toward controversy. What could possibly go wrong? Unsurprisingly, the case is generally reviled by those who can be overly generalized as “the Left” and praised by those who can likewise be overly generalized as “the Right.” The Hobby Lobby case was so contentious precisely because it was reflective of a number of larger concerns in the popular American psyche—fear of corporate personhood, the impact of religious freedom claims in an era of expanding reproductive rights for women (and the impact of the latter, and other progressive social movements, on the former), and the ability of religiously affiliated individuals and institutions to exist and navigate within a cultural atmosphere, which is progressively more hostile to the views of conservative and traditional institutions
The effect of noise correlations on randomized benchmarking
Among the most popular and well studied quantum characterization,
verification and validation techniques is randomized benchmarking (RB), an
important statistical tool used to characterize the performance of physical
logic operations useful in quantum information processing. In this work we
provide a detailed mathematical treatment of the effect of temporal noise
correlations on the outcomes of RB protocols. We provide a fully analytic
framework capturing the accumulation of error in RB expressed in terms of a
three-dimensional random walk in "Pauli space." Using this framework we derive
the probability density function describing RB outcomes (averaged over noise)
for both Markovian and correlated errors, which we show is generally described
by a gamma distribution with shape and scale parameters depending on the
correlation structure. Long temporal correlations impart large nonvanishing
variance and skew in the distribution towards high-fidelity outcomes --
consistent with existing experimental data -- highlighting potential
finite-sampling pitfalls and the divergence of the mean RB outcome from
worst-case errors in the presence of noise correlations. We use the
Filter-transfer function formalism to reveal the underlying reason for these
differences in terms of effective coherent averaging of correlated errors in
certain random sequences. We conclude by commenting on the impact of these
calculations on the utility of single-metric approaches to quantum
characterization, verification, and validation.Comment: Updated and expanded to include full derivation. Related papers
available from http://www.physics.usyd.edu.au/~mbiercuk/Publications.htm
Explaining enhanced logical consistency during decision making in autism
The emotional responses elicited by the way options are framed often results in lack of logical consistency in human decision making. In this study, we investigated subjects with autism spectrum disorder (ASD) using a financial task in which the monetary prospects were presented as either loss or gain. We report both behavioral evidence that ASD subjects show a reduced susceptibility to the framing effect and psycho-physiological evidence that they fail to incorporate emotional context into the decision-making process. On this basis, we suggest that this insensitivity to contextual frame, although enhancing choice consistency in ASD, may also underpin core deficits in this disorder. These data highlight both benefits and costs arising from multiple decision processes in human cognition
Emerging treatments for essential thrombocythemia
In 1934, Epstein and Goedel used the term hemorrhagic thrombocythemia to describe a disorder characterized by permanent elevation of a platelet count to more than three times normal, hyperplasia of megakaryocytes, and the tendency for venous thrombosis and spontaneous hemorrhage. Over the last 75 years, and particularly in the past 6 years, major progress has been made in our understanding of essential thrombocythemia (ET) and its pathogenesis with the identification of the highly prevalent JAK-2 V617F and other mutations. Current management of this condition is based upon historical data and with treatments that have not changed significantly for nearly two decades. This study discusses this and recent progress, highlighting exciting new data with old and new drugs, as well as which patients in particular should be evaluated for these new therapies
Misconceptions Of Employee Turnover: Evidence-Based Information For The Retail Grocery Industry
Employee turnover rates are higher in the retail grocery industry in comparison to other industries. This level of turnover produces demoralizing effects on the grocery industry’s profitability. The lack of evidence-based information regarding causes of employee turnover may result in senior level leadership within the retail grocery industry formulating retention strategies based upon conjecture. Basing retention strategies on turnover misconceptions may be costly and actually fail to reduce turnover. For these reasons, this study sought to fill the knowledge gap by providing the grocery industry with evidence-based information on the topic of employee turnover. In an effort to provide a better understanding of the factors that support an engaged workforce, data from 151 frontline retail grocery employees’ gathered perceptions of their work environment, burnout, and turnover intentions. The participating employees represented one grocery chain in Western New York. The key finding was that value conflicts have a strong, statistically significant relationship with cynicism, which in turn increases the likelihood for employee turnover. Making use of this evidence-based information may help in creating strategies for a more engaged workforce and retaining the most valuable employees
Matching concepts across HOL libraries
Many proof assistant libraries contain formalizations of the same
mathematical concepts. The concepts are often introduced (defined) in different
ways, but the properties that they have, and are in turn formalized, are the
same. For the basic concepts, like natural numbers, matching them between
libraries is often straightforward, because of mathematical naming conventions.
However, for more advanced concepts, finding similar formalizations in
different libraries is a non-trivial task even for an expert.
In this paper we investigate automatic discovery of similar concepts across
libraries of proof assistants. We propose an approach for normalizing
properties of concepts in formal libraries and a number of similarity measures.
We evaluate the approach on HOL based proof assistants HOL4, HOL Light and
Isabelle/HOL, discovering 398 pairs of isomorphic constants and types
Physical-Layer Security: Combining Error Control Coding and Cryptography
In this paper we consider tandem error control coding and cryptography in the
setting of the {\em wiretap channel} due to Wyner. In a typical communications
system a cryptographic application is run at a layer above the physical layer
and assumes the channel is error free. However, in any real application the
channels for friendly users and passive eavesdroppers are not error free and
Wyner's wiretap model addresses this scenario. Using this model, we show the
security of a common cryptographic primitive, i.e. a keystream generator based
on linear feedback shift registers (LFSR), can be strengthened by exploiting
properties of the physical layer. A passive eavesdropper can be made to
experience greater difficulty in cracking an LFSR-based cryptographic system
insomuch that the computational complexity of discovering the secret key
increases by orders of magnitude, or is altogether infeasible. This result is
shown for two fast correlation attacks originally presented by Meier and
Staffelbach, in the context of channel errors due to the wiretap channel model.Comment: 12 pages, 5 figures. Submitted and accepted to the International
Conference on Communications (ICC) 2009. v2: equivalent to the version that
will be published in the conference proceedings. Has some altered notation
from version 1 as well as slight changes in the wording to make the paper
more readable and easier to understan
Patterns, causes, and consequences of marine larval dispersal
Quantifying the probability of larval exchange among marine populations is key to predicting local population dynamics and optimizing networks of marine protected areas. The pattern of connectivity among populations can be described by the measurement of a dispersal kernel. However, a statistically robust, empirical dispersal kernel has been lacking for any marine species. Here, we use genetic parentage analysis to quantify a dispersal kernel for the reef fish Elacatinus lori, demonstrating that dispersal declines exponentially with distance. The spatial scale of dispersal is an order of magnitude less than previous estimates—the median dispersal distance is just 1.7 km and no dispersal events exceed 16.4 km despite intensive sampling out to 30 km from source. Overlaid on this strong pattern is subtle spatial variation, but neither pelagic larval duration nor direction is associated with the probability of successful dispersal. Given the strong relationship between distance and dispersal, we show that distance-driven logistic models have strong power to predict dispersal probabilities. Moreover, connectivity matrices generated from these models are congruent with empirical estimates of spatial genetic structure, suggesting that the pattern of dispersal we uncovered reflects long-term patterns of gene flow. These results challenge assumptions regarding the spatial scale and presumed predictors of marine population connectivity. We conclude that if marine reserve networks aim to connect whole communities of fishes and conserve biodiversity broadly, then reserves that are close in space (<10 km) will accommodate those members of the community that are short-distance dispersers.We thank Diana Acosta, Alben David, Kevin David, Alissa Rickborn, and Derek Scolaro for assistance with field work; Eliana Bondra for assistance with molecular work; and Peter Carlson for assistance with otolith work. We are grateful to Noel Anderson, David Lindo, Claire Paris, Robert Warner, Colleen Webb, and two anonymous reviewers for comments on this manuscript. This work was supported by National Science Foundation (NSF) Grant OCE-1260424, and C.C.D. was supported by NSF Graduate Research Fellowship DGE-1247312. All work was approved by Belize Fisheries and Boston University Institutional Animal Care and Use Committee. (OCE-1260424 - National Science Foundation (NSF); DGE-1247312 - NSF Graduate Research Fellowship)Published versio
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