2,268 research outputs found
Pre-K Counts in Pennsylvania for Youngsters' Early School Success: Authentic Outcomes for an Innovative Prevention and Promotion Initiative
Examines the research base for the efficacy of early childhood education. Evaluates Pennsylvania's Pre-K Counts programs, including participants' characteristics, impact and quality of programs and partnerships, lessons learned, and recommendations
Comment on 'Stability of the semiclassical Einstein equation'
Some mathematical errors of the paper commented upon [W.-M. Suen, Phys. Rev.
D 40, (1989) 315] are corrected.Comment: 3 pages, LaTeX, reprinted from Phys. Rev. D 50 (1994) 545
Media as watchdogs: The role of news media in electoral competition
We develop an equilibrium model to analyze the role of the media in electoral competition. When policy payoffs are state-dependent, party policies do not converge to the median voter's ideal policy if the media report only party policies. News analysis about the state, though possibly biased, can discipline off-equilibrium deviations and make the parties adopt more centrist policies. Since voters are rational, the party favored by the media need not win with a higher probability. Instead, media bias may reduce the effectiveness of electoral competition and lead to more polarized policies. © 2009 Elsevier B.V. All rights reserved.postprin
The classical-quantum divergence of complexity in modelling spin chains
The minimal memory required to model a given stochastic process - known as
the statistical complexity - is a widely adopted quantifier of structure in
complexity science. Here, we ask if quantum mechanics can fundamentally change
the qualitative behaviour of this measure. We study this question in the
context of the classical Ising spin chain. In this system, the statistical
complexity is known to grow monotonically with temperature. We evaluate the
spin chain's quantum mechanical statistical complexity by explicitly
constructing its provably simplest quantum model, and demonstrate that this
measure exhibits drastically different behaviour: it rises to a maximum at some
finite temperature then tends back towards zero for higher temperatures. This
demonstrates how complexity, as captured by the amount of memory required to
model a process, can exhibit radically different behaviour when quantum
processing is allowed.Comment: 9 pages, 3 figures, comments are welcom
Marital transfer and intra-household allocation: A Nash-bargaining analysis
This paper explores the implications of inter-generational marital transfers on the allocation of resources within a conjugal household. Adopting a Nash-bargaining framework with alternative models of the threat points, it is argued that parents have greater incentive to make transfers to a married child than to a single child because of the efficiency gains from joint consumption and production of family public goods and because of the increase in bargaining power of the child in the allocation of private consumption. Such transfers also enhance marital stability by increasing the efficiency gains from marriage. © 2002 Elsevier Science B.V. All rights reserved.postprin
MACS: Multi-agent COTR system for Defense Contracting
The field of intelligent multi-agent systems has expanded rapidly in the recent past. Multi-agent architectures and systems are being investigated and continue to develop. To date, little has been accomplished in applying multi-agent systems to the defense acquisition domain. This paper describes the design, development, and related considerations of a multi-agent system in the area of procurement and contracting for the defense acquisition community
Spontaneous Interlayer Charge Transfer near the Magnetic Quantum Limit
Experiments reveal that a confined electron system with two equally-populated
layers at zero magnetic field can spontaneously break this symmetry through an
interlayer charge transfer near the magnetic quantum limit. New fractional
quantum Hall states at unusual total filling factors such as \nu = 11/15 (= 1/3
+ 2/5) stabilize as signatures that the system deforms itself, at substantial
electrostatic energy cost, in order to gain crucial correlation energy by
"locking in" separate incompressible liquid phases at unequal fillings in the
two layers (e.g., layered 1/3 and 2/5 states in the case of \nu = 11/15).Comment: 4 pages, 4 figures (1 color) included in text. Related papers at
http://www.ee.princeton.edu/~hari/papers.htm
Surveying structural complexity in quantum many-body systems
Quantum many-body systems exhibit a rich and diverse range of exotic
behaviours, owing to their underlying non-classical structure. These systems
present a deep structure beyond those that can be captured by measures of
correlation and entanglement alone. Using tools from complexity science, we
characterise such structure. We investigate the structural complexities that
can be found within the patterns that manifest from the observational data of
these systems. In particular, using two prototypical quantum many-body systems
as test cases - the one-dimensional quantum Ising and Bose-Hubbard models - we
explore how different information-theoretic measures of complexity are able to
identify different features of such patterns. This work furthers the
understanding of fully-quantum notions of structure and complexity in quantum
systems and dynamics.Comment: 9 pages, 5 figure
The Shapiro Conjecture: Prompt or Delayed Collapse in the head-on collision of neutron stars?
We study the question of prompt vs. delayed collapse in the head-on collision
of two neutron stars. We show that the prompt formation of a black hole is
possible, contrary to a conjecture of Shapiro which claims that collapse is
delayed until after neutrino cooling. We discuss the insight provided by
Shapiro's conjecture and its limitation. An understanding of the limitation of
the conjecture is provided in terms of the many time scales involved in the
problem. General relativistic simulations in the Einstein theory with the full
set of Einstein equations coupled to the general relativistic hydrodynamic
equations are carried out in our study.Comment: 4 pages, 7 figure
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