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SUMMARY An optimization problem which provides a new characterization for ridge regression is discussed. A variant of this optimization problem leads to a new family of biased estimators that includes the Stein estimation method and principal components regression as particular cases. The whole approach is illustrated on the basis of real data sets.  相似文献   
905.
Three agricultural regions of France: Three types of pluriactivity   总被引:2,自引:0,他引:2  
In France, the new Common Agricultural Policy will have different regional impacts. There are three types of regions based on agricultural development. The first type is where farms are able to carry on a modernization process; the second type where farms are threatened in spite of their modernization, and the third type where farms are unable to be modernized. These three types of regions are represented in France by Picardy, Languedoc and Savoy. Each region is developing a particular form of pluriactivity in accordance with its own agricultural development. Picardy is setting up a business pluriactivity which uses agricultural resources to increase non-agricultural activities. Languedoc undergoes a rural development pluriactivity by using non-agricultural resources for its modernization. Savoy represents a rural pluriactivity of survival, in which the close combination between agricultural and non-agricultural activities permits the maintenance of rural many-faceted businesses.The three kinds of pluriactivity are very unlike. They show that, in France, agricultural development will in future be linked to rural development to a far greater extent.  相似文献   
906.
 This paper studies the topological approach to social choice theory initiated by G. Chichilnisky (1980), extending it to the case of a continuum of agents. The social choice rules are continuous anonymous maps defined on preference spaces which respect unanimity. We establish that a social choice rule exists for a continuum of agents if and only if the space of preferences is contractible. We provide also a topological characterization of such rules as generalized means or mathematical expectations of individual preferences. Received: 30 November 1994/Accepted: 22 April 1996  相似文献   
907.
The well-known Meixner class (Meixner, 1934) of probabilities on R has been extended recently to R d (Pommeret, 1996). This generalized Meixner class corresponds to the simple quadratic natural exponential families characterized by Casalis (1996). Following Lancaster (1975), the present paper offers a characterization of the joint probability of a randomvector ( X, Y ) such that the two variables X and Y on R d belong to the multidimensional Meixner class and fulfil a bi-orthogonality condition involving orthogonal polynomials. The joint probabilities, called Lancaster probabilities, are characterized by two sequences of orthogonal polynomials with respect to the margins and a sequence of expectations of products. Some multivariate probabilities are studied, namely the Poisson-Gaussian and the gamma-Gaussian.  相似文献   
908.
The Collaborative Demonstration Program for Homeless Individuals is providing an opportunity for several community agencies in the United States to explore innovative intervention and treatment strategies to address the needs of homeless people with co-occurring (mental illness and substance abuse) disorders. This cooperative agreement, funded jointly by the Center for Mental Health Services (CMHS) and the Center for Substance Abuse Treatment (CSAT), is a $3 million project supporting programs in various community agencies to develop, document, and evaluate programs for persons who are homeless with co-occurring disorders to be used as models in other communities. The program models include: Assertive Community Treatment, Psychosocial Rehabilitation, Therapeutic Community, and an integrated treatment model. The first phase of the two-phase project funded 16 programs in the U.S. to develop manuals within their primary treatment modalities for homeless people with co-occurring disorders. For Phase II of the project, six of the 16 model programs were competitively selected to demonstrate program impact through formal program evaluation efforts. The data derived from the various projects will be compiled into a compendium of information for state agencies and community service providers throughout the U.S.  相似文献   
909.
This review of the governance practices of twenty-five public-private partnerships involved in addressing a broad range of community health needs shows that governance in public-private community partnerships departs significantly from traditional notions of institutional governance. Governance structures and degrees of progress toward governance goals vary widely and appear to be systematically related to the organization, composition, location, and activity of each partnership.  相似文献   
910.
The article provides evidence that there is a relationship between government debt and interest rates via the demand for money. This relationship is examined through the wealth effect of government debt on money demand, and the robustness of the results is tested by the use of extreme bound analysis in addition to standard econometric techniques. We find that OLS regression shows government debt fnfecting the demand for money positively, implying that Federal government debt is net wealth. In addition, the extreme bound analysis shows that the estimates of the government debt coefficient are robust under alternative specifications of the Goldfeld model.  相似文献   
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