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101.
A Lotto Systems bet allows the player to nominate n numbers from which (s)he believes the winning six numbers will be drawn, and to bet on all combinations of six of these n numbers. Assume that the winning six numbers come from the nominated n. How many combinations must be entered to guarantee that one combination will include at least five of the winning six numbers? The problem is generalized in this paper, and the method of simulated annealing is used to find solutions for various situations. The case where two supplementary numbers are drawn after the initial six winning numbers is also considered.  相似文献   
102.
Mothers' time‐use patterns were compared in families in which infants spent more than 30 hours per week in child care (In‐Care group; n= 143) versus 0 hours per week (At‐Home group; n= 183) from birth to 6 months of age. In‐Care group mothers spent about 12 fewer hours per week interacting with their infants, for about 32% less time; fathers of these infants were more involved in caregiving. The groups did not differ in the quality of mother‐infant interaction. In the In‐Care group, quantity of interaction was related to greater separation anxiety and concerns about effects of maternal employment. Time‐use data were not related to child outcomes at 15 months of age. Results suggest that the effect of extensive time spent apart on the quantity and quality of mother‐infant interaction may be smaller than anticipated.  相似文献   
103.
Abstract Accounts of poverty generally fall into either “individualist” or “structuralist” camps. Often these are seen as irreconcilable and incompatible competing perspectives. This paper integrates individualist and structuralist accounts of poverty by examining the relationship between “person poverty” and “place poverty” in nonmetropolitan and metropolitan labor markets, using a multilevel framework. I fashion a general model of poverty production and allocation, drawing on the labor market ecology perspective. After a discussion of this perspective, I develop a multilevel framework for analyzing data from the 1990 Census PUMS‐L sample, STF‐3c, and other sources to show how compositional and contextual factors affect households' likelihoods of being in poverty. These multilevel models also allow us to estimate the degree to which labor market conditions influence the magnitude of household labor supply characteristics. Results suggest that both compositional and contextual factors contribute to the metro‐nonmetro difference in poverty rates, and that the effects of employment vary in accordance with labor market characteristics.  相似文献   
104.
This experimental, layered, mixed‐genre narrative folds my biographical experiences into a critical reading of a cultural performance involving cowboys and Indians in a small Montana town in summer 2000. Informed by critical race theory and poststructuralism, this narrative attempts to deconstruct racial stereotypes associated with Native Americans and their presence in America's movies and popular culture.  相似文献   
105.
The rise in the number of asylum seekers in Australia presents considerable challenges to the state as they are a self‐selected, demand‐driven group, whose numbers, country of origin, ethnic background, and social demographic characteristics cannot be determined in advance of their arrival. People who apply for protection at the border are regarded primarily as illegal immigrants, and only secondarily as asylum seekers, and the illegality of their entry has become the primary factor in the way they are treated by the state, rather than their need for protection. Two streams of asylum seekers and two streams of refugees have been created. There are marked differences in the treatment given while claims for protection are examined and once decisions have been made in their favor. This article examines the development of asylum policy in Australia and sets the discussion within a review of the number of people who have applied for and been granted protection in recent years.  相似文献   
106.
This article is a summary of the literature published in 2001 related to career counseling and career development. The review is designed to provide information to both career practitioners and researchers, with the focus on integration of practice and research. This summary of literature is organized around 5 primary areas: (a) career development, (b) career and vocational theories, (c) career interventions, (d) career assessment, and (e) professional issues. Within the framework of this review, attention is also given to contextual factors including gender, race or ethnicity, sexual orientation, and nationality.  相似文献   
107.
Arrow's axioms for social welfare functions are shown to be inconsistent when the set of alternatives is the nonnegative orthant in a multidimensional Euclidean space and preferences are assumed to be either the set of analytic classical economic preferences or the set of Euclidean spatial preferences. When either of these preference domains is combined with an agenda domain consisting of compact sets with nonempty interiors, strengthened versions of the Arrovian social choice correspondence axioms are shown to be consistent. To help establish the economic possibility theorem, an ordinal version of the Analytic Continuation Principle is developed. Received: 4 July 2000/Accepted: 2 April 2001  相似文献   
108.
109.
The Hohokam of southern Arizona are noted for greater duration of settlement than other major agricultural traditions in the archaeological record of the southwestern United States, including the Anasazi and Mogollon. The 40,000 square mile area inhabited by the Hohokam is marked by low elevation desert basins, but encompasses a range of topographic and climatic variability that shaped opportunities for prehistoric farming technologies. Irrigation from rivers was frequently associated with the longterm persistence of individual sites, while floodwater farming along ephemeral drainages was more often correlated with continuous occupation of hydrologically favored zones. Renewal of fields by waterborne nutrients and efficient practices in the use of natural resources countered the limited mobility options afforded by the Hohokam environment.In spite of a restrictive agricultural setting and an essentially static suite of productive technologies over many centuries, relationships among population, settlement, and landuse were redefined in evolving social and economic configurations. An example from the Tucson Basin illustrates differentiated patterns of settlement and agriculture arising in conjunction with increased levels of population and territorial integration in the late prehistoric period. Community organization among interrelated settlements incorporated a diversity of topographic zones and agricultural technologies in this high-risk context for prehistoric cultivators.  相似文献   
110.
A general form for characterizing inverse Gaussian and Wald distributions, based on their respective length-biased distributions, is introduced. Further results for characterizations of the gamma distribution, the negative binomial distribution and some mixtures of them by using their lengthbiased distributions are establised.  相似文献   
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