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961.
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   
962.
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   
963.
In light of the Armitage-Doll multistage carcinogenesis theory, this paper examines the assumption that an additive relative risk relationship is indicative of two carcinogens that affect the same stage in the cancer process. We present formulas to compute excess cancer risks for a variety of patterns for limited exposure durations to two carcinogens that affect the first and penultimate stages; and using an index of synergy proposed by Thomas (1982), we find a number of these patterns to produce additive, or nearly additive, relative risk relationships. The consistent feature of these patterns is that the two exposure periods are of short duration and occur close together.  相似文献   
964.
 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   
965.
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   
966.
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   
967.
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   
968.
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   
969.
Parenting by men who abuse women: issues and dilemmas   总被引:2,自引:0,他引:2  
Summary Enabling children of abused women to maintain a positive relationshipwith the perpetrator is extremely complex in the light of thepotential danger for women and children and the conflictingneeds, interests and rights of different family members. Nevertheless,we can no longer ignore the role of abusive men as fathers.Holding such men accountable for their children's well-beingmay, under certain conditions, contribute to the healthier emotionaldevelopment of their children. This article critically discussesthis controversial issue by examining available literature on(a) children's perceptions of their violent fathers, (b) abusivemen as parents, qualifications for abusive men's access to theirchildren, and (d) intervention with children of abusive menand their fathers.  相似文献   
970.
Outsourcing and union power   总被引:1,自引:0,他引:1  
The outsourcing of union work and jobs either diffuses or diminishes union membership, depending on perspective and situation. The correlation of trends in union membership to trends in union power, while less than perfect, has until recently been relatively strong over the past sixteen years. The fact that as diverse a sample of unions as AFSCME, SEIU, and UAW have chosen to make outsourcing a prominent labor/public relations issue suggests that the correlation continues to be perceived by the union movement to be significant, notwithstanding the efforts of the “new” leadership of the AFL-CIO to break that link with respect to union political power by “taxing” member unions and their members to contribute both money and militancy to the 1996 election cycle. Although outsourcing may lead only to the diffusion of union membership either within or between unions, as opposed to the diminution of union membership, this fact has not received a great deal of attention. The net effect on total union membership of outsourcing from one union employer to another union employer is unclear, although the effect on the membership of the union at the outsourcing employer is not. The redistribution of membership within a union as a result of outsourcing is likely to have little immediate impact on union power. However, as even the best case scenario presented above suggests, it may have significant long-run deleterious effects on union bargaining power by taking labor out of a sheltered market and putting it into potentially competitive market. This is particularly likely to be the case when outsourcing (1) places the outsourced work into a different industry or wage contour and (2) creates the possibility of moving from sole-source to multiplesource supplier arrangements. The redistribution of membership between unions as a result of outsourcing is unlikely to have a major impact on union power broadly defined. It can have, however, serious deleterious effects in terms of the power of an individual union, as suggested in my “competitive case” scenario. The fact that one union’s losses due to outsourcing may be another union’s gain is of little consolation to the losing union. That act, in and of itself, may make the threat of outsourcing a potential union “Achilles heel” at the bargaining table by placing it into competition with some other, perhaps unknown, union as well as possibly nonunion competition. The most obvious threat to union power comes from outsourcing that diminishes union membership overall by transferring jobs from union to nonunion employers. The willingness and ability of employers to move work/jobs entirely out of the orbit of union control constitutes, in terms of power and particularly union bargaining power, a revisitation of the phenomenon of the “runaway shop.” It may also be viewed as a proactive form of hiring permanent replacements for (potentially) striking workers. The union options in dealing with such a challenge are to endeavor to preclude outsourcing through legislation or collective bargaining or to chase the work by organizing the unorganized, hopefully with the help of the unionized outsourcing employer. Neither option may be easy, but as the 1996 auto industry negotiations suggest, the former may be less difficult than the latter. The possibility that outsourcing from union to nonunion employer may provide unions with the power to organize from the top (outsourcer) down (outsourcee) cannot be entirely ignored as the issue of supplier “neutrality” reportedly was raised in the 1996 auto negotiations. The adverse effects of outsourcing on union political and financial power, by virtue of its impact on the level or distribution of union membership, can and may well be offset by an increase in union activism—as measured by dues levels, merger activity, organizing commitment, and political action. The adverse effects of outsourcing on union bargaining power are more problematical from the union standpoint. The effect of outsourcing, whatever its rationale or scenario, appears to be to put union labor back into competition. Thus, outsourcing constitutes yet another challenge to the labor movement in its ongoing and seemingly increasingly unsuccessful battle to take and keep U.S. union labor out of competition by proving itself able and willing to organize to the extent of the market and standardizing wages in that market.  相似文献   
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