5,894 research outputs found
Racial Profiling and the War on Terror: Changing Trends and Perspectives
Minorities in the United States have often been treated unfairly by law enforcement agencies. Prior to the September 11, 2001, terrorist attack on the United States, Blacks were the main victims of racial profiling. Since the terrorist attack, however, Arabs and Muslims are becoming the primary targets for profiling by law enforcement agencies. There are some remarkable similarities between the profiling of Blacks and the profiling of Arabs and Muslims. In both cases, the fundamental problems with racial profiling are that it violates the civil liberties of innocent people and denies minorities the equal protection of the law. The War on Terror has redefined racial profiling. It has not only led to a shift in the target population, but it has also changed the ways in which racial profiling is conducted
The impact of leverage reduction on the equity risk level of the firm : an exploratory study of French firms
Although it is admitted that financing decisions affect the equity risk of the firm, few studies have been dedicated to the analysis of the relationship between risk and leverage. In fact, to our knowledge, no study has addressed the question of whether leverage reduction has an effect on equity risk. This exploratory paper addresses this issue using data on French firms. The results of the study show that leverage reduction significantly reduces equity risk. However, an indirect test of the relative importance of this effect indicates that the reduction may not lead to shifts in risk classes. In other words, asset risk is the more important risk factor.leverage reduction; equity risk; beta; risk class
Structure of Anomalies of 4d SCFTs from M5-branes, and Anomaly Inflow
We study the 't Hooft anomalies of four-dimensional superconformal field
theories that arise from M5-branes wrapped on a punctured Riemann surface. In
general there are two independent contributions to the anomalies. There is a
bulk term obtained by integrating the anomaly polynomial of the world-volume
theory on the M5-branes over the Riemann surface; this contribution knows about
the punctures only through its dependence on the Euler characteristic of the
surface. The second set of contributions comes from local data at the
punctures; these terms are independent from the bulk data of the surface. Using
anomaly inflow in M-theory, we describe the general structure of the anomalies
for cases when the four-dimensional theories preserve N=2 supersymmetry. We
additionally discuss the anomalies corresponding to (p,q) punctures in N=1
theories.Comment: version 2, 38 pages. We simplified the discussion of the inflow
procedure with punctures and removed the details of the explicit computation
of the puncture anomalies in order to focus on arguing the main new ideas.
Added clarification on main resul
Linear Quivers and N=1 SCFTs from M5-branes
We study a class of N=1 quiver gauge theories build out of vector multiplets
and matter multiplets in the fundamental and bifundamental representations. We
argue that these theories flow to interacting SCFTs in the IR and calculate
their central charges. We exhibit a type IIA brane construction which at low
energies is described by these SCFTs. This also leads to a natural description
of the theories in terms of M5-branes on a punctured sphere.Comment: 21 pages, 5 figure
Structural Transformation in Developed and Developing Countries
Differences in key features of the development process across rich and poor countries can provide clues to the sources of the large variation of cross-country income. Kuznets included structural transformation as one of six stylized facts of economic development, nding that developed countries all followed the same process. In this paper, I compare structural transformation processes in developed and developing countries. I nd that developing countries follow distinct structural transformation paths that deviate from that followed by developed countries. A puzzling nding is the presence of substantial sectoral changes during times of economic stagnation or decline. --Africa,Asia,Latin America,Structural Transformation,Economic Development,Structural Change
From Concession to Joint Venture Agreement: Restructuring Mineral Agreements – A Case Study from Ghana
Discrete Optimization Methods for Group Model Selection in Compressed Sensing
In this article we study the problem of signal recovery for group models.
More precisely for a given set of groups, each containing a small subset of
indices, and for given linear sketches of the true signal vector which is known
to be group-sparse in the sense that its support is contained in the union of a
small number of these groups, we study algorithms which successfully recover
the true signal just by the knowledge of its linear sketches. We derive model
projection complexity results and algorithms for more general group models than
the state-of-the-art. We consider two versions of the classical Iterative Hard
Thresholding algorithm (IHT). The classical version iteratively calculates the
exact projection of a vector onto the group model, while the approximate
version (AM-IHT) uses a head- and a tail-approximation iteratively. We apply
both variants to group models and analyse the two cases where the sensing
matrix is a Gaussian matrix and a model expander matrix.
To solve the exact projection problem on the group model, which is known to
be equivalent to the maximum weight coverage problem, we use discrete
optimization methods based on dynamic programming and Benders' Decomposition.
The head- and tail-approximations are derived by a classical greedy-method and
LP-rounding, respectively
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