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111.
We analyze the wealth ejfects of the Texaco racial discrimination lawsuit both on the shareholders of Texaco and its major U.S. competitors. Employing a comprehensive data set which included every case docket entry and every Wall Street Journal article on the case as an experimental stimulus, our findings suggest that the overall cost of the case to Texaco shareholders exceeded $500 million, that Texaco's tribulations had little, if any, impact on the share prices of its major competitors, and that Wall Street Journal coverage of the case was highly correlated with significant changes in Texaco stock prices. This last finding provides significant support for Hite 's suppostion that newspaper editors “key ” on ex post stock price changes in selecting the events to be covered in the next day's edition. The authors are grateful to Kee Chung for helpful comments on earlier drafts and also acknowlege the help-ful assistance of the staff of the law library at the Cecil C. Humphreys School of Law at The University of Memphis.  相似文献   
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Most real-world shapes and images are characterized by high variability- they are not rigid, like crystals, for example—but they are strongly structured. Therefore, a fundamental task in the understanding and analysis of such image ensembles is the construction of models that incorporate both variability and structure in a mathematically precise way. The global shape models introduced in Grenander's general pattern theory are intended to do this. In this paper, we describe the representation of two-dimensional mitochondria and membranes in electron microscope photographs, and three-dimensional amoebae in optical sectioning microscopy. There are three kinds of variability to all of these patterns, which these representations accommodate. The first is the variability in shape and viewing orientation. For this, the typical structure is represented via linear, circular and spherical templates, with the variability accomodated via the application of transformations applied to the templates. The transformations form groups: scale, rotation and translation. They are locally applied throughout the continuum and of high dimension. The second is the textural variability; the inside and outside of these basic shapes are subject to random variation, as well as sensor noise. For this, statistical sensor models and Markov random field texture models are used to connect the constituent structures of the shapes to the measured data. The third variability type is associated with the fact that each scene is made up of a variable number of shapes; this number is not assumed to be known a priori. Each scene has a variable number of parameters encoding the transformations of the templates appropriate for that scene. For this, a single posterior distribution is defined over the countable union of spaces representing models of varying numbers of shapes. Bayesian inference is performed via computation of the conditional expectation of the parametrically defined shapes under the posterior. These conditional mean estimates are generated using jump-diffusion processes. Results for membranes, mitochondria and amoebae are shown.  相似文献   
114.
This article compares in regression models the effects of occupational status of both fathers and mothers simultaneously upon the attainment of men and women in the Irish Republic. The sample matches male respondents from the 1973/1974 Irish Mobility Study with the labour active female sibling next closest in age. Since the analysis compares working siblings and each 'matched pair' shares the same family origin characteristics, the problems attendant upon using a sample originally of men only are partially avoided. The results advance beyond previous research since, rather than separate models by gender, models include parents and children of both genders, allowing direct rather than indirect evaluation of gender-based determinants of occupational attainment. Both fathers and mothers significantly affect children's attainment, in ways that vary by the child's gender. The results highlight the salience of mothers' attainment for their children and question the 'mainstream' model of equivalent mechanisms of occupational attainment for both genders. Models of social mobility that consider men and women as special instances of a general perspective provide the most fruitful approach for further development.  相似文献   
115.
Sources of drug information among adolescent students   总被引:1,自引:0,他引:1  
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed.  相似文献   
116.
This study investigates the extent and nature of housing affordability for elderly nonmetropolitan female heads of household using data from the Panel Study of Income Dynamics. The results indicate that over one-third of elderly nonmetropolitan female heads of household experience housing poverty and that those who rent, who have fair to poor health, and who are minorities are particularly vulnerable. Housing affordability, measured by the concept of housing poverty, identifies households struggling to meet basic needs while the conventional 25% of income for housing expenditures ratio identifies a larger population. The findings suggest the need for multifaceted public policies to address the problem of housing poverty. Her research interests include housing affordability, housing and community vitality, and decision making. She received her Ph.D. from Purdue University. Sooyoun Park is in the same department as a Project Assistant on a USDA-funded research project entitled “Housing Affordability in Rural Areas,” which is a joint project between Nebraska and Wisconsin. Her research interests focus on housing management behavior in relation to housing expenditure burden. She received her Ph.D. from the University of Nebraska-Lincoln.  相似文献   
117.
A theory of policy differentiation in single issue electoral politics   总被引:1,自引:0,他引:1  
Voter preferences are characterized by a parameter s (say, income) distributed on a set S according to a probability measure F. There is a single issue (say, a tax rate) whose level, b, is to be politically decided. There are two parties, each of which is a perfect agent of some constituency of voters, voters with a given value of s. An equilibrium of the electoral game is a pair of policies, b 1 and b 2, proposed by the two parties, such that b i maximizes the expected utility of the voters whom party i represents, given the policy proposed by the opposition. Under reasonable assumptions, the unique electoral equilibrium consists in both parties proposing the favorite policy of the median voter. What theory can explain why, historically, we observe electoral equilibria where the ‘right’ and ‘left’ parties propose different policies? Uncertainty concerning the distribution of voters is introduced. Let {F(t)} t ε T be a class of probability measures on S; all voters and parties share a common prior that the distribution of t is described by a probability measure H on T. If H has finite support, there is in general no electoral equilibrium. However, if H is continuous, then electoral equilibrium generally exists, and in equilibrium the parties propose different policies. Convergence of equilibrium to median voter politics is proved as uncertainty about the distribution of voter traits becomes small.  相似文献   
118.
The suitability of autoregressive fractionally integrated moving average (ARFIMA) processes for the modeling of US aggregate output is examined. We consider the two most widely used methods for the estimation of the fractionally differencing parameter and discuss the empirical results obtained by applying these methods to the quarterly post-war real GNP as well as to the quarterly post-war real GNP per capita. Contrary to previous findings, we conclude that evidence for a fractional degree of integration is poor.  相似文献   
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