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1.
From the inception of the proportional representation movement it has been an issue whether larger parties are favored at
the expense of smaller parties in one apportionment of seats as compared to another apportionment. A number of methods have
been proposed and are used in countries with a proportional representation system. These apportionment methods exhibit a regularity
of order, as discussed in the present paper, that captures the preferential treatment of larger versus smaller parties. This
order, namely majorization, permits the comparison of seat allocations in two apportionments. For divisor methods, we show
that one method is majorized by another method if and only if their signpost ratios are increasing. This criterion is satisfied
for the divisor methods with power-mean rounding, and for the divisor methods with stationary rounding. Majorization places
the five traditional apportionment methods in the order as they are known to favor larger parties over smaller parties: Adams,
Dean, Hill, Webster, and Jefferson.
Received: 5 August 2000/Accepted: 24 October 2001 相似文献
2.
Measures of Multigroup Segregation 总被引:3,自引:0,他引:3
In this paper we derive and evaluate measures of multigroup segregation. After describing four ways to conceptualize the measurement of multigroup segregation—as the disproportionality in group (e.g., race) proportions across organizational units (e.g., schools or census tracts), as the strength of association between nominal variables indexing group and organizational unit membership, as the ratio of between–unit diversity to total diversity, and as the weighted average of two–group segregation indices—we derive six multigroup segregation indices: a dissimilarity index (D), a Gini index (G), an information theory index (H), a squared coefficient of variation index (C), a relative diversity index (R), and a normalized exposure index (P). We evaluate these six indices against a set of seven desirable properties of segregation indices. We conclude that the information theory index H is the most conceptually and mathematically satisfactory index, since it alone obeys the principle of transfers in the multigroup case. Moreover, H is the only multigroup index that can be decomposed into a sum of between– and within–group components. 相似文献
3.
Fire and restoration of the largest urban forest of the world in Rio de Janeiro City,Brazil 总被引:1,自引:1,他引:0
National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity. 相似文献
4.
Carmen Fernández Eduardo Ley Mark F. J. Steel 《Journal of the Royal Statistical Society. Series C, Applied statistics》2002,51(3):257-280
Summary. We model daily catches of fishing boats in the Grand Bank fishing grounds. We use data on catches per species for a number of vessels collected by the European Union in the context of the Northwest Atlantic Fisheries Organization. Many variables can be thought to influence the amount caught: a number of ship characteristics (such as the size of the ship, the fishing technique used and the mesh size of the nets) are obvious candidates, but one can also consider the season or the actual location of the catch. Our database leads to 28 possible regressors (arising from six continuous variables and four categorical variables, whose 22 levels are treated separately), resulting in a set of 177 million possible linear regression models for the log-catch. Zero observations are modelled separately through a probit model. Inference is based on Bayesian model averaging, using a Markov chain Monte Carlo approach. Particular attention is paid to the prediction of catches for single and aggregated ships. 相似文献
5.
A finite mixture model using the multivariate t distribution has been shown as a robust extension of normal mixtures. In this paper, we present a Bayesian approach for inference about parameters of t-mixture models. The specifications of prior distributions are weakly informative to avoid causing nonintegrable posterior distributions. We present two efficient EM-type algorithms for computing the joint posterior mode with the observed data and an incomplete future vector as the sample. Markov chain Monte Carlo sampling schemes are also developed to obtain the target posterior distribution of parameters. The advantages of Bayesian approach over the maximum likelihood method are demonstrated via a set of real data. 相似文献
6.
Work accommodation for people with multiple chemical sensitivity 总被引:1,自引:1,他引:0
Multiple chemical sensitivity (MCS) is a term used to describe allergic-like reactions to chemicals that represent everyday exposures in industrialized countries. It is sometimes associated with electromagnetic sensitivity, and both conditions are most likely engendered by environmental exposures. Prevalence studies suggest that chemical sensitivity affects 12-15% of the US population and that it crosses age, socio-economic status and racial lines. Electromagnetic sensitivity is less understood, but affects a portion of those with chemical sensitivity. Persons with these environmental sensitivities often experience difficulties with health care, housing and work. Workplace barriers result in significant disability, with ensuing financial loss and isolation for the worker. We examined work accommodations for 100 persons with self-reported MCS and its relation to life satisfaction. Results are discussed in terms of accommodating invisible disabilities that challenge industrial capitalism. 相似文献
7.
The 1998 Korean Survey of Family Income and Expenditures was used to examine the overall consumption and saving behavior of Korean baby boomers and compared the differences in consumption and saving behavior between older and younger boomers. The t -test results indicated that the younger boomers allocated a significantly higher percentage of their expenditures on food away from home, household appliances, transportation and communication than did the older boomers, whereas the older boomers spent higher amounts and allocated larger budget shares on their children's education than did the younger boomers. The results of Ordinary Least-Squares (OLS) regression analysis showed that, holding other factors constant, older boomers not only spent significantly more in the total consumption expenditures and education expenditures, but older boomers also saved significantly less than did younger boomers. 相似文献
8.
The study investigates Swedish male and female social workers’ assessments and help-giving strategies towards single parents applying for income support. The study was carried out with the help of a vignette distributed as a mail questionnaire. Results show that social workers tend to conform to assessments and help-giving strategies that are consistent with expectations linked to their own gender role. 相似文献
9.
We examine the labor-cost savings associated with privatization by comparing earnings and employment trends of public and
private sector refuse workers. Findings suggest that high union earnings for workers in the public sector are a source of
labor-cost savings in the refuse industry. Evidence on job changers does not indicate that earnings for this group of workers
are a compensating differential. Metropolitan area employment findings suggest that municipalities are less likely to use
union refuse workers in the public sector when a relatively small percentage of area residents belong to a union.
The authors thank Jacqueline Agesa, Keith Bender, Maria Crawford, and Richard Perlman for valuable suggestions. Research assistance
from Eric Blackburn is greatly appreciated. 相似文献
10.