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241.
This paper considers a likelihood ratio test for testing hypotheses defined by non-oblique closed convex cones, satisfying the so called iteration projection property, in a set of k normal means. We obtain the critical values of the test using the Chi-Bar-Squared distribution. The obtuse cones are introduced as a particular class of cones which are non-oblique with every one of their faces. Examples with the simple tree order cone and the total order cone are given to illustrate the results.  相似文献   
242.
Over the last 40 years, the Sahel has seen a long-term downward trend in rainfall. The importance of ecological variables as factors affecting child survival in rural subsistence societies has already been emphasized, but little empirical evidence has been gathered to support this. This paper presents a comparative event history analysis aimed at understanding how rainfall variations may influence child mortality in two neighbouring countries, Burkina Faso and Mali. These countries are similar in terms of population dynamics, economy, livelihood, child mortality and rainfall conditions (i.e. strong south–north decreasing rainfall gradient). Individual data for both countries came from two detailed nationally representative retrospective surveys conducted in 2000. Rainfall data for the 1960–1998 time period were obtained from the Climatic Research Unit. This study shows that child survival in each country is related to specific patterns of rainfall variation across livelihood regions, highlighting the complex nature of environmental causality of child mortality.  相似文献   
243.
It has been reported that familiarity or incidental similarities with a stranger influenced an individual’s behavior. However, the effect of the sense of geographical proximity believing that someone comes from the same area that somebody has never been examined. Three field experiments examined this effect on donations to humanitarian organizations. In the first study, participants were asked by a confederate to donate food products to a humanitarian organization. In Study 2, participants were asked by confederates to donate money for children. In Study 3, donation boxes were displayed in bakeries with a message that invited customers to donate money for children. In all the studies, participants were led to believe that they would be helping people in need or people who live in their national or local geographic area. Results showed that donations were higher in the geographical proximity condition. This “neighborhood effect” was discussed.  相似文献   
244.
Editorial     
Drawing on texts written by young people aged 14–17 years in a school context in response to an invitation to write a page describing themselves and their vision of Ireland and to use the reverse side creatively for drawings, poems or songs, this article illustrates the methodological difficulties of exploring globalization and individualization in such texts. The indicators of globalization were global entertainment and consumer culture, global technology, references to international travel, and global concerns. The indicators of individualization were the absence of references to structural location, or the presence of references to choices, hopes or plans and related images. There were insurmountable methodological difficulties in differentiating between individualization in these terms and stereotypical ways of ‘doing boy/girl’. Hence, the typology that was created focussed on the global content of the main texts and back pages and their gendered content.  相似文献   
245.
A decision under ‘complete uncertainty’ is one where the decision maker knows the set of possible outcomes for each decision, but cannot assign probabilities to those outcomes. This way, the problem of ranking decisions is reduced to a problem of ranking sets of outcomes. All rankings that have emerged in the literature in this domain imply transitivity. In the current study, transitivity is subjected to an empirical evaluation in two experiments, where subjects are asked to choose between sets of monetary consequences. After analysis with a Bayes Factor, very few violations of transitivity were found. It can be concluded that transitivity seems a plausible condition for the ranking of sets of monetary consequences.  相似文献   
246.
In this paper we introduce a new extension for the Birnbaum–Saunder distribution based on the family of the epsilon-skew-symmetric distributions studied in Arellano-Valle et al. (J Stat Plan Inference 128(2):427–443, 2005). The extension allows generating Birnbaun–Saunders type distributions able to deal with extreme or outlying observations (Dupuis and Mills, IEEE Trans Reliab 47:88–95, 1998). Basic properties such as moments and Fisher information matrix are also studied. Results of a real data application are reported illustrating good fitting properties of the proposed model.  相似文献   
247.
This article shows that if an allocation rule can be implemented with unlimited information certification, then it can also be implemented with limited information certification if the designer can use ambiguous communication mechanisms, and if agents are averse to ambiguity in the sense of maxmin expected utility. The reverse implication is true if there is a single agent and a worst outcome.  相似文献   
248.
Despite the well‐documented importance of parental sensitivity for child development, there is a lack of consensus regarding how best to assess it. We investigated the factor structure of maternal caregiving behavior as assessed at 12 months by the Maternal Behavior Q‐Sort (Pederson & Moran) with 274 mother‐infant dyads. Subsequently, we examined associations between these empirically‐derived dimensions and child attachment, assessed in the home and laboratory (final N = 157). Three dimensions of maternal behavior were identified, corresponding fairly closely to Ainsworth's original scales. They were labeled Cooperation/Attunement, Positivity, and Accessibility/Availability. Only Cooperation/Attunement consistently predicted home‐based attachment at 15 months and 2 years, and at comparable strength to the overall sensitivity score, suggesting that this construct may be central to sensitivity. At 18 months, compared to their primarily secure counterparts, different types of laboratory‐assessed insecure attachment were associated with different patterns of maternal behavior. Mothers in avoidant relationships (n = 18) were low on Cooperation/Attunement and Accessibility/Availability, but fairly high on Positivity. Mothers of disorganized infants (n = 11) were Cooperative/Attuned but somewhat less Positive toward, and less Accessible/Available to, their infants. A multidimensional approach to parental behavior may facilitate the identification of parenting precursors of insecure parent‐child relationships.  相似文献   
249.
Thrushes (Turdus spp., Turdidae) are among the most common frugivorous birds in urban areas around the world, where they disperse the seeds of a variety of plant species. We studied the abundance, habitat use, foraging behavior and diet of four thrush species (Turdus rufiventris, T. amaurochalinus, T. leucomelas, and T. albicollis) in a suburban area in south Brazil. Abundance, habitat use and foraging behavior were based on birds surveyed along a 3,240 m transect crossing open (formed by lawns, streets, and buildings) and forested areas. Diet was based on fecal samples collected from mist-netted birds. Turdus rufiventris was the most abundant species, followed by T. amaurochalinus, T. leucomelas, and T. albicollis. All species used forest fragments more frequently than expected by chance. A total of 91.8% (n = 147) of the fecal samples contained fruit remains, while 42.2% contained only animal matter. Most of the foraging records were on the ground, where birds got mainly invertebrates. Fruits and invertebrates were eaten more frequently in open than in forested areas. A total of 25 seed morfospecies were found in the droppings, including five exotic plant species. Thrushes overlapped widely in the fruit composition of their diets. The high abundance and degree of frugivory, coupled with the frequent use of forest patches, indicate that thrushes are among the great bird contributors to the seed dispersal occurring in urban forest patches, potentially influencing the vegetation dynamics of such habitats so important for the maintenance of the biodiversity in urban areas.  相似文献   
250.
Adult refugee claimants experience several well‐documented post‐migratory challenges. Little is known about the resettlement process for refugee claimant families with children. This study reports on 75 open‐ended, in‐depth interviews with refugee claimant families in Montreal about their resettlement challenges and their proposed solutions to them. These interviews were conducted with 33 dyads and triads of children and parents attending a paediatric hospital. Experiences accessing formal and informal child care in Montreal were addressed. Subsequently, a comparative policy analysis was conducted on residency eligibility criteria for child care subsidization. Twenty‐eight out of 39 parents (73%) report a lack of informal or formal child care and 15 out of 33 families (39%) propose improving access to formal child care services. They describe a lack of informal child care as a result of reduced social networks, and affordability as a barrier to formal child care services. Refugee claimants are not eligible for subsidized child care in Quebec. A comparative policy analysis within Canada and comparable countries reveals that this situation is not unique to Quebec. However, most provinces and European countries offer child care subsidies to refugee claimants. Refugee claimants should qualify for child care subsidies. Social workers and community organizations should consider their clients' child care needs in designing programmes and services.  相似文献   
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