4,333 research outputs found
Self-Similar Random Processes and Infinite-Dimensional Configuration Spaces
We discuss various infinite-dimensional configuration spaces that carry
measures quasiinvariant under compactly-supported diffeomorphisms of a manifold
M corresponding to a physical space. Such measures allow the construction of
unitary representations of the diffeomorphism group, which are important to
nonrelativistic quantum statistical physics and to the quantum theory of
extended objects in d-dimensional Euclidean space. Special attention is given
to measurable structure and topology underlying measures on generalized
configuration spaces obtained from self-similar random processes (both for d =
1 and d > 1), which describe infinite point configurations having accumulation
points
Corruption and Reform: An Introduction
The United States today, according to most studies, is among the least corrupt nations in the world. But America's past was checkered with political scandal and widespread corruption that would not seem unusual compared with the most corrupt developing nation today. We construct a "corruption and fraud index" using word counts from a large number of newspapers for 1815 to 1975, supplemented with other historical facts. The index reveals that America experienced a substantial decrease in corruption from 1870 to 1920, particularly from the late-1870s to the mid-1880s and again in the 1910s. At its peak in the 1870s the "corruption and fraud index" is about five times its level from the end of the Progressive Era to the 1970s. If the United States was once considerably more corrupt than it is today, then America's history should offer lessons about how to reduce corruption. How did America become a less corrupt polity, economy, and society? We review the findings and insights from a series of essays for a conference volume, Corruption and Reform: Lessons from America's History, for which this paper is the introduction that attempt to understand the remarkable evolution of corruption and reform in U.S. history.
Women, Children, and Industrialization in the Early Republic: Evidence from the Manufacturing Censuses
The first half of the nineteenth century was a critical juncture regarding the emergence of female participation in the market economy, the increase in the wage of females relative to that of adult males, and the evolution of large scale firms in both mechanized and non-mechanized industries. We present the first systematic and comprehensive description of these events as they evolved in the states of the Northeast to 1850. Our sources are primarily samples taken from three early censuses and reports of manufacturing, 1820, 1832, and 1850. Our principal findings are: (1) that women and children composed a large share (over 40% in 1832) of the entire manufacturing labor force during the initial period of industrialization in the U.S., but that this share began a secular decline as early as 1840; (2) that the wage of females (and boys) relative to that of adult males rose wherever large scale manufacturing establishments spread and that by 1850 this ratio had risen to almost 90% its long-term level; (3) that the labor force participation of young unmarried women in the industrial counties of the Northeast was, in 1832, high by late nineteenth century standards; and (4) that the employment of females and boys was closely associated with production processes used by large-scale establishments. Women and children had been a previously under-utilized and large segment of the potential labor force, and their harnessing by manufacturing was a critical factor in the industrialization of the Northeast.
The Relative Productivity Hypothesis of Industrialization: The American Case, 1820-1850
The American Northeast industrialized rapidly from about 1820 to 1850, while the South remained agricultural. Industrialization in the Northeast was substantially powered during these decades by female and child labor, who comprised about 45% of the manufacturing work force in 1832. Wherever manufacturing spread in the Northeast, the wages of females and children relative to those of adult men increased greatly from levels in the agricultural sector which were previously quite low. Our hypothesis of early industrialization is that such development proceeds first in areas whose agriculture, for various reasons, puts a low value on females and children relative to adult men. The lower the "relative productivity" of females and children in the pre-industrial agricultural or traditional economy the earlier will manufacturing evolve, the proportionately greater will the relative wages for females and children increase, and the relatively more manufactured goods will the economy produce. A two-sector model which incorporates a difference in "relative productivity" between two economies is used to develop seven propositions relating to the process of early industrialization. Data from two early censuses of manufactures, 1832 and 1850, and other sources provide evidence for our hypothesis, demonstrating, for example, the low relative productivity of females and children in the Northeast agricultural sector, and the increase in relative wages for these laborers with industrialization. We conclude that factors with low relative productivity in agriculture were instrumental in the initial adoption of the factory system and of industrialization in general in the U.S., and we believe these results are applicable to contemporary phenomena in developing countries.
Unconstrained Astrometric Orbits for Hipparcos Stars with Stochastic Solutions
A considerable number of astrometric binaries whose positions on the sky do
not obey the standard model of mean position, parallax and linear proper
motion, were observed by the Hipparcos satellite. Some of them remain
non-discovered, and their observational data have not been properly processed
with the more adequate astrometric model that includes nonlinear orbital
motion. We develop an automated algorithm based on "genetic optimization", to
solve the orbital fitting problem with no prior information about the orbital
elements is available (from, e.g., spectroscopic data or radial velocity
monitoring). We test this method on Hipparcos stars with known orbital
solutions in the catalog, and further apply it to stars with stochastic
solutions, which may be unresolved binaries. At a confidence level of 99%,
orbital fits are obtained for 65 stars, most of which have not been known as
binary. A few of the new probable binaries with A-type primaries with periods
444-2015 d are chemically peculiar stars, including Ap and \lambda Boo type.
The anomalous spectra of these stars are explained as admixture of the light
from the unresolved, sufficiently bright and massive companions. We estimate
the apparent orbits of four stars which have been identified as members of the
300 Myr-old UMa kinematic group. Another four new nearby binaries may include
low-mass M-type or brown dwarf companions. Similar astrometric models and
algorithms can be used for binary stars and planet hosts observed by SIM
PlanetQuest and Gaia
Effects of Premature Birth and/or Low Birthweight on Developmental Outcomes
Advances in neonatal technology have improved survival rates of children born at lower and lower birthweight and after fewer and fewer weeks of gestation. However, these children are at increased risk of experiencing developmental delays. As weeks of gestation and birthweight decrease, the risk of developmental impairment and severity increases. Yet to be determined is whether premature birth and low birthweight (LBW) effect development differentially, and if the combined, have an additive effect on developmental outcomes. The first part of this study aimed to examine the independent effects of preterm birth and LBW in children at risk for developmental delays. Using the Battelle Developmental Inventory, Second Edition (BDI-2), differences in overall developmental quotient (DQ) scores and domain scores (i.e., adaptive, personal-social, communication, motor, cognitive) were assessed. In Part 1, were noted different developmental profiles for children born premature and/or LBW. Additionally, premature birth and low birthweight (PLBW) children exhibited the greatest impairment in all areas of development evaluated compared to their premature, LBW, and full term peers. The second part of this study aimed to examine the predictive value of weeks of gestation, birthweight, age, gender, and race on developmental outcomes. For Part 2, weeks of gestation, birthweight, age, gender, and race predicted statistically significant impairments in all the areas of development assessed with to varying degrees. These findings support the institution of early intervention, before clinical manifestations appear, and the importance of highly individualized interventions
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