Persistent inequality when learning requires a minimal standard of living

This paper studies the persistence of wealth and utility inequality in a dynamicmodel of skill acquisition with complete credit markets and rational, perfectly altruistic,dynastic utility-maximization, when efficient learning requires a minimal standardof living. The main result is that, if the minimal standard of living is not triviallysmall, at any stationary equilibrium without intergenerational mobility there are?poor?, unskilled and ?rich?, skilled dynasties. Members of rich dynasties inherit morefrom their parents than members of poor dynasties. The former in general acquireskill, while the latter remain unskilled, and - most importantly - members of rich familiesalso enjoy strictly higher utility than members of poor dynasties. This paper studies the persistence of wealth and utility inequality in a dynamicmodel of skill acquisition with complete credit markets and rational, perfectly altruistic,dynastic utility-maximization, when efficient learning requires a minimal standardof living. The main result is that, if the minimal standard of living is not triviallysmall, at any stationary equilibrium without intergenerational mobility there are?poor?, unskilled and ?rich?, skilled dynasties. Members of rich dynasties inherit morefrom their parents than members of poor dynasties. The former in general acquireskill, while the latter remain unskilled, and - most importantly - members of rich familiesalso enjoy strictly higher utility than members of poor dynasties

Ontology-Based MEDLINE Document Classification

An increasing and overwhelming amount of biomedical information is available in the research literature mainly in the form of free-text. Biologists need tools that automate their information search and deal with the high volume and ambiguity of free-text. Ontologies can help automatic information processing by providing standard concepts and information about the relationships between concepts. The Medical Subject Headings (MeSH) ontology is already available and used by MEDLINE indexers to annotate the conceptual content of biomedical articles. This paper presents a domain-independent method that uses the MeSH ontology inter-concept relationships to extend the existing MeSH-based representation of MEDLINE documents. The extension method is evaluated within a document triage task organized by the Genomics track of the 2005 Text REtrieval Conference (TREC). Our method for extending the representation of documents leads to an improvement of 17% over a non-extended baseline in terms of normalized utility, the metric defined for the task. The SVMlight software is used to classify documents

The Witt Ring of a Curve with Good Reduction over a Non-dyadic Local Field

In this work, we present a generalization to varieties and sheaves of the fundamental ideal of the Witt ring of a field by defining a sheaf of fundamental ideals $\tilde{I}$ and a sheaf of Witt rings $\tilde{W}$ in the obvious way. The Milnor conjecture then relates the associated graded of $\tilde{W}$ to Milnor K-theory and so allows the classical invariants of a bilinear space over a field to be extended to our setting using \'etale cohomology. As an application of these results, we calculate the Witt ring of a smooth curve with good reduction over a non-dyadic local field

The Construction and Operation of a Reaction Time Machine

The Encyclopedia Britannica states that One of the cardinal problems of psychophysics is the measurement of the duration of the mental processes . To accomplish this purpose it is necessary to have a chronograph or chronoscope measuring in small fractions of a second with connections suitable to the experiment

\u3ci\u3eAcrobasis\u3c/i\u3e Shoot Moth (Lepidoptera: Pyralidae) Infestation-Tree Height Link in a Young Black Walnut Plantation

Acrobasis shoot moth infestations were evaluated in a young black walnut progeny test for 4 years, from ages 3 to 6. Infestation levels were greatest on the largest trees in the fourth and fifth year after plantation establishment, and were declining by the sixth year. Acrobasis infestation appears to be a problem primarily on young trees less than 2.5 m in height. There was no evidence for genetic resistance to Acrobasis infestation in black walnut

Updated estimate of the duration of the meningo-encephalitic stage in gambiense human African trypanosomiasis

Background: The duration of the stages of HAT is an important factor in epidemiological studies and intervention planning. Previously, we published estimates of the duration of the haemo-lymphatic stage 1 and meningo-encephalitic stage 2 of the gambiense form of human African trypanosomiasis (HAT), in the absence of treatment. Here we revise the estimate of stage 2 duration, computed based on data from Uganda and South Sudan, by adjusting observed infection prevalence for incomplete case detection coverage and diagnostic inaccuracy. Findings: The revised best estimate for the mean duration of stage 2 is 252 days (95% CI 171–399), about half of our initial best estimate, giving a total mean duration of untreated gambiense HAT infection of approximately 2 years and 2 months. Conclusions: Our new estimate provides improved information on the transmission dynamics of this neglected tropical disease in Uganda and South Sudan. We stress that there remains considerable variability around the estimated mean values, and that one must be cautious in applying these results to other foci

Extraction of many-body configurations from nonlinear absorption in semiconductor quantum wells

Detailed electronic many-body configurations are extracted from quantitatively measured timeresolved nonlinear absorption spectra of resonantly excited GaAs quantum wells. The microscopic theory assigns the observed spectral changes to a unique mixture of electron-hole plasma, exciton, and polarization effects. Strong transient gain is observed only under co-circular pump-probe conditions and is attributed to the transfer of pump-induced coherences to the probe

Comparison of Fermi-LAT and CTA in the region between 10-100 GeV

The past decade has seen a dramatic improvement in the quality of data available at both high (HE: 100 MeV to 100 GeV) and very high (VHE: 100 GeV to 100 TeV) gamma-ray energies. With three years of data from the Fermi Large Area Telescope (LAT) and deep pointed observations with arrays of Cherenkov telescope, continuous spectral coverage from 100 MeV to $\sim10$ TeV exists for the first time for the brightest gamma-ray sources. The Fermi-LAT is likely to continue for several years, resulting in significant improvements in high energy sensitivity. On the same timescale, the Cherenkov Telescope Array (CTA) will be constructed providing unprecedented VHE capabilities. The optimisation of CTA must take into account competition and complementarity with Fermi, in particularly in the overlapping energy range 10$-$100 GeV. Here we compare the performance of Fermi-LAT and the current baseline CTA design for steady and transient, point-like and extended sources.Comment: Accepted for Publication in Astroparticle Physic

Exploring the development of team identification.

The article discusses a study investigating the development of identification with sports teams, with particular focus given to the application of social identity theory and the psychological continuum model (PCM). The development of internal meaning attached to the team and external actions such as searching for team-related information and promoting the team to others is examined, and the influence of media on attitude formation is commented on. A review of previous literature on the topic is also provided