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81.
Environmental and human health issues associated with outdoor air pollution, such as ozone, sulfur dioxide, and other pollutants in metropolitan regions, are an area of growing concern for both policy officials and the general public. Increasing attention from the news media, new health data, and public debate over the effectiveness of clean air regulations have raised the importance of air quality in the public consciousness. While public perceptions of air quality have been studied thoroughly dating back to the 1960s, little empirical research has been conducted to explain the spatial aspects of these perceptions, particularly at the local level. Although recent studies suggest characteristics of local setting are important in shaping perceptions of air quality, the roles of proximity, neighborhood characteristics, and location have not been clarified. This study seeks to improve understanding of the major factors shaping public perceptions of air quality by examining the spatial pattern of local risk perception, the role of socioeconomic characteristics in forming these perceptions, and the relationship between perceived and scientifically measured air pollution. First, we map the spatial pattern of local air quality perceptions using Geographic Information Systems (GIS) across the Dallas and Houston metropolitan areas. Next, we explain these perceptions through local contextual factors using both bivariate correlations and multivariate regression analysis. Results indicate that perceptions of air quality in the study areas are not significantly correlated with air quality based on readings of air monitoring stations. Instead, perceptions appear to be influenced by setting (urban vs. rural), state identification, access to information, and socioeconomic characteristics such as age, race, and political identification. We discuss the implications of the findings and provide direction on how further research can provide a deeper understanding of the local contextual factors influencing public perceptions.  相似文献   
82.
The present empirical study applies the methodology of information theory to the problem of assessing and separating capital market risk, which is separated into its systematic and unsystematic components. Monthly return relatives for all securities traded on the New York Stock Exchange are examined for the period 1926 to 1971, which is segmented into six 7-year subperiods. The securities are combined into portfolios of various sizes and ranked. It is concluded that although both systematic and unsystematic risks have increased over the 45-year interval—particularly between the pre-1940 and post-1940 periods—they have maintained their relative share of the total risk over the same period.  相似文献   
83.
One of the characteristics of modern industrial development is the emergence of a new typology of accidents whose effects can be spread, in space as well as in time, well beyond the borders of the installations where they occur, sometimes impacting the local population and the environment in a catastrophic fashion. This is the result of a number of factors that have changed the risk profile of modern industrial activities. For a number of reasons, the developing countries have proved to be more vulnerable to industrial disasters. Three of the most catastrophic industrial accidents—Bhopal, San Juan de Ixhuatepec, and Cubatão—occurred in developing countries, claiming thousands of lives. During the 1970s and 1980s the higher degree of public visibility of industrial hazards as a result of serious accidents, led to the creation, especially in the more industrialized countries, of regulations for greater control over industrial activities, either by means of new laws or by updating existing legislation. Some of these regulations were designed to improve the response to accidents with potential impacts outside the industrial sites. This article attempts to describe the current status and identify the shortcomings of off‐site emergency planning for hazardous industrial areas in Brazil. The most important problems are the lack of specific legislation and the absence of awareness and active participation of public authorities. The experience of an off‐site emergency planning process for a Brazilian industrial area is presented. This experience illustrates how difficult it is to prepare and implement emergency planning processes in an industrializing country.  相似文献   
84.
This paper investigates how workers’ “economic struggle” determines the “democratic class struggle,” and extends socialist electoral constituency. This paper argues that political outcomes, namely, electoral behavior, may not be understood independently of the labor process, especially its most militant manifestation, strikes. Rather than follow the customary conceptual dichotomy between the sphere of production and the political sphere, it is suggested that both strike activity and electoral participation are compatible political strategies that, under specific historical circumstances, may jointly determine the fate of the Socialist party. The leading question is how did the wave of strikes in post World War I Italy affect the electoral power of the Italian Socialist party, in comparison with another mass party, the Popular Catholic Party. Hierarchical Linear Modeling (HLM) is employed to analyze census, strike, and electoral data. It is found that strike activity and electoral democracy increased the electoral power of the Socialist party, whereas they had little effect on the power of the Catholic party. It is suggested that this was due to the Catholic non-revolutionary program which was ambivalent about the political role of strikes. It is concluded that the socialists’ political success was determined by their dual political strategy in both spheres, electoral participation, and organizing strikes.  相似文献   
85.
86.
The purpose of this paper is firstly to investigate the distribution of two parent low income families in England and Wales and Scotland for see to what extent they differ, and secondly to examine the relative importance of certain contributing factors in determining the distributions. From an analysis of Family Expenditure Survey data it is found that although it is difficult to arrive at statistically verifiable conclusions about the nature of the distributions, interesting qualitative observations can be made.  相似文献   
87.
This paper is designed to bring into focus the numerous modeling attempts to analyze commodity price stabilization that have recently appeared. The studies examined begin with the Waugh-Oi-Massell framework and advance to econometric commodity modeling. Such a critique is considered necessary: None of the studies examined has overcome the myriad of problems that analysts have pointed out as essential for assessing the welfare outcomes of price stabilization schemes. As a consequence, stabilization analyses for similar commodities have produced conflicting results regarding predicted welfare outcome. The present appraisal attempts to provide a unity of direction to this work by (1) comparing recieved studies of a theoretical, empirical, and econometric modeling nature, and (2) suggesting possibilities for improving modeling analyses.  相似文献   
88.
This study is based on repeated interviews with twelve heterosexual female commercial sex workers (SWs) in Perth. These informants deploy, with various degrees of success, strategies to demarcate ‘work-sex’, with its socially ascribed stigma, from ‘non-work sex’. Such strategies inhibit the spread of HIV at work but, ironically, increase the risk of HIV transmission during non-work sex. SWs recognise this risk and construct a variety of rationales to reduce their fear of contracting HIV and justify their strategies of demarcating work-sex from non-work sex. Efforts to reduce the risk of HIV infection among Perth SWs would seem to depend upon addressing not only these strategies of demarcation but these rationales in a supportive environment that recognises the creative complexities of their lives.  相似文献   
89.
90.
Objectives . Property rights are central to debates about natural resource policy. Governments traditionally have been seen as the appropriate custodians of natural resources for their citizens. More recently, many argue the privatization of property rights will ensure that users have incentives to manage their resources well. Common property, to the extent it is discussed at all, is seen as leading to the tragedy of the commons. We evaluate these claims by assessing property rights and forest conditions in two private and three communal forests in Guatemala. Methods . Data on biological and social phenomena from five forests (151 plots) and their associated communities were collected using the International Forestry Resources and Institutions Research Program protocols. Ordinary least squares regression was used to analyze four models. We examined t -scores for differences in coefficients for the different models. Results . The models demonstrate that de jure property rights are not a powerful predictor of variations among the sampled forests. Conclusions . We argue that de facto institutions and their enforcement are much more important than de jure property rights to forest management. Communities holding a forest in common can, under certain circumstances, create institutions to manage their resources as successfully as—or more successfully than—private owners.  相似文献   
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