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891.
This article provides a new maximum-likelihood estimator forselection models with dichotomous dependent variables when identicalfactors affect the selection equation and the equation of interest.Such situations arise naturally in game-theoretic models whereselection is typically nonrandom and identical explanatory variablesinfluence all decisions under investigation. When identicalexplanatory variables influence selection and a subsequent outcomeof interest, the commonly used Heckman-type estimators identifyfrom distributional assumptions about the residuals alone. Whenits own identifying assumption is reasonable, the new estimatorallows the researcher to avoid the painful choice between identifyingfrom distributional assumptions alone and adding a theoreticallyunjustified variable to the selection equation in a mistakenattempt to "boost" identification. The article uses Monte Carlomethods to compare the small-sample properties of the estimatorwith those of the Heckman-type estimator and ordinary probit.  相似文献   
892.
This research reports on public opinion surveys on intergovernmentaland federal issues conducted in Canada, Mexico, and the UnitedStates in March and April 2003. In all three countries, respondentsmost often see their federal government as being the least effective,least efficient, and least trustworthy. Respondents from Canadaappear least supportive of their federal government and mostsupportive of their local governments; those from Mexico appearmost supportive of their state governments; respondents fromthe United States appear more "balanced" in their support ofthe various orders of government. Also, far greater regionaldifferences in opinion exist in Canada than in Mexico or theUnited States. Support for more decentralized federalism isfound to be strong in all these federal countries. This researchalso updates long-term trend data for the United States. Comparedwith respondents from previous years, U.S. respondents in 2003showed a measurable uplick in support for the federal government,compared with state and local governments. This support seemsto be a carryover from the terrorist attacks of 11 September2001.  相似文献   
893.
Don't lose sleep     
Allen E 《Time》2001,157(14):83
  相似文献   
894.
This paper directs itself to the impact of American social science on the writings of Alva and Gunnar Myrdal on the role of education and social science in modern industrial democracy. After a brief sketch of the Myrdals' role in the development of Swedish welfare reforms and of their intellectual contacts in the United States during the 1930's, the paper outlines four theoretical dilemmas of modernity to the solution of which education and social research was seen to contribute: the relationships between facts and values, the individual and the collective, child rearing and social change, and theory and practice. The paper concludes by tracing the articulation of these themes in the Social Democratic Party school reform proposals of 1948.  相似文献   
895.
We report here the results of mtDNA analysis of remains exhumed in July, 1995 from Mt. Olivet Cemetery in Kearney, Nebraska, that are thought to be those of Jesse James. The remains were poorly preserved, presumably due to wet and slightly acidic soil conditions, and insufficient DNA for analysis was obtained from two bone samples. However, two of four teeth, and two hairs recovered in 1978 from the original burial site on the James Farm, did yield reproducible mtDNA sequences. These mtDNA sequences from the teeth and hairs were all identical, suggesting that they came from the same individual; furthermore, this mtDNA sequence was identical to mtDNA sequences determined from blood samples from two maternal relatives of Jesse James. Therefore, either the remains are indeed those of Jesse James, or they are from an unrelated individual who, by chance, happens to have the same mtDNA sequence. To assess the probability that an unrelated individual would have the same sequence, we searched the forensic mtDNA database, and found that this sequence does not appear among the 2426 mtDNA sequences therein. Hence, the mtDNA analysis supports the identification of the exhumed remains from Mt. Olivet Cemetery as those of Jesse James.  相似文献   
896.
897.
The nature and extent of the use of blank pistols in Hamburg (according to the Hamburg crime statistics about 300 to 400 such cases per year; 34 cases involving head and neck wounds from 1989 to 1999 were investigated at our institute; among these 8 suicides, no homicide) as well as patterns of injuries caused by close distance blank pistol shots were analysed. 7 of these cases are described in detail. The results of our studies corroborate the warning statements made by many criminological and medico-legal experts regarding the danger inherent in these allegedly harmless weapons. Blank cartridge pistols can, when shot from a close distance, cause most severe injuries involving penetration into body cavities and bodily organs (especially in the head and neck), and even perforation of the skull. Therefore, we call for a much stricter control of weapons of this kind.  相似文献   
898.
899.
Combined homicide-suicides have been classified based on the psychopathology of the perpetrator and the nature of the relationship between perpetrator and victim(s). To further understand the nature of this tragic phenomenon and to test the validity and practicality of a previously suggested classification system, investigators systematically collected data on all combined homicide-suicide events that occurred in Galveston County, Texas over a continuous 18-year period (n = 20). The most common psychopathological finding for perpetrators was high serum alcohol levels that suggested intoxication. Most combined homicide-suicides fell into one of the relational categories and most of these, as predicted, were of the consortial type, possessive subtype. As expected, due to the small sample size, the less common types of combined homicide-suicide were not represented in this sample.  相似文献   
900.
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