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991.
The objective study of self‐recognition, with a mirror and a mark applied to the face, was conducted independently by Gallup (1970) for use with chimpanzees and monkeys, and by Amsterdam (1972) for use with infant humans. Comparative psychologists have followed the model (and assumptions) set by Gallup, whereas developmental psychologists have followed a different model (e.g., Lewis & Brooks‐Gunn, 1979). This article explores the assumptions in the definitions and methods of self‐recognition assessments in the 30 years since these initial studies, and charts the divergence between the developmental mark test and the comparative mark test. Two new studies, 1 with infant chimpanzees and 1 with infant humans, illustrate a reconciliation of the 2 approaches. Overt application of the mark, or other procedures related to how the mark is discovered, did not enhance mirror self‐recognition. In contrast, maternal scaffolding appears to enhance performance, perhaps by eliciting well‐rehearsed verbal responses (i.e., naming self). When comparable testing procedures and assessment criteria are used, chimpanzee and human infants perform comparably. A combined developmental comparative approach allows us to suggest that mirror self‐recognition may be based on a specific aspect of mental representation, the cognitive ability to symbolize. 相似文献
992.
As a number of new nations emerged in the early nineties, there has been a spurt in regulatory initiatives in transition countries
toward nation building and socio-economic reforms. A key prerequisite to policy changes is an understanding of the related
patterns and policies. This paper provides an overview of the smoking trends in transition nations, broken by gender and age,
and the antismoking policies in place. In particular, four different types of non-price policies are studied. Comparisons
with the rest of the world show that transition countries do not fare badly in terms of implementing antismoking policies
and are, in fact, better in some cases than other countries. However, greater smoking prevalence for some population subgroups
in transition nations suggests that either some other socio-economic factors influencing smoking prevalence might be at play
or there might be some enforcement issues with the policies in place. 相似文献
993.
Frances K. Goldscheider 《Demography》1995,32(3):471-480
This paper argues that the field of household and family demography serves a critical role in the development of our understanding of the determinants and consequences of population trends. Like the community, families and households are situated between the two levels at which demographic research is ordinarily conducted — the individual and the nation-state. The results of the papers in this issue are used to illustrate the critical ways that intergenerational and gender relationships shape demographic processes. 相似文献
994.
A study of three-dimensional curves 总被引:2,自引:2,他引:0
K. V. Mardia A. J. Baczkowski X. Feng P. A. Millner 《Journal of applied statistics》1996,23(1):139-148
In certain abnormalities of spinal shape, the long axis of the spine moves out of the median sagittal plane, producing both an axial torsion and a lateral deviation out of the usual front-back plane. Clinicians need to be able to assess rapidly and accurately whether or not an individual has such an abnormality. In this paper, we examine several case studies. These are analyzed using some simple summary statistics, and the use of these methods to infer abnormality is demonstrated. Using a simple fitted model for the data, an angular estimate of abnormality is obtained. Empirical measures of abnormality based on the eigenvalues of the covariance matrix are also determined. These methods are applied to a number of individuals for whom the surface spinal profiles have been recorded and who have been assessed as normal or abnormal by clinicians. 相似文献
995.
G. Casella K. L. Mengersen C. P. Robert D. M. Titterington 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2002,64(4):777-790
Summary. We consider the construction of perfect samplers for posterior distributions associated with mixtures of exponential families and conjugate priors, starting with a perfect slice sampler in the spirit of Mira and co-workers. The methods rely on a marginalization akin to Rao–Blackwellization and illustrate the duality principle of Diebolt and Robert. A first approximation embeds the finite support distribution on the latent variables within a continuous support distribution that is easier to simulate by slice sampling, but we later demonstrate that the approximation can be very poor. We conclude by showing that an alternative perfect sampler based on a single backward chain can be constructed. This alternative can handle much larger sample sizes than the slice sampler first proposed. 相似文献
996.
First an overview is given of the secular decline of infant mortality in Austria between 1820 and 1950 is given. Second the study analyses the historical regional differences of infant mortality in Austria comparing data for all 99 political districts (Politische Bezirke) for the period 1900 to 1950. The most important results are: At the turn of the 19th century infant mortality rates were generally lower in Alpine than in non-alpine regions and lower in cities than in their surrounding areas. This geographical pattern which remained constant until the 1950s was solely determined by differences in post-neonatal mortality rates. Plausible explanations for these regional differences are discussed.En premier lieu cette étude fournit une vue d'ensemble du déclin séculaire de la mortalité infantile en Autriche en 1820 et 1950. Elle analyse ensuite les différences régionales de mortalité infantile en comparant les données des 99 districts politiques (Politische Bezirke) autrichiens, de 1900 à 1950. Les principaux résultats sont les suivants: à la fin du XIXe siècle les taux de mortalité infantile étaient en général plus faibles dans les régions alpines que dans les autres et plus faibles dans les villes que dans les aires adjacentes. Ce modèle géographique, qui est resté le même jusqu'en 1950, était uniquement déterminé par les différences entre les taux de mortalité post-néonatale. Des explications plausibles de ces différences régionales sont discutées ici. 相似文献
997.
The need for old‐age security coverage in rural areas of many developing countries is rapidly increasing for several reasons, including population ageing and the weakening of family support networks. These trends have generated intense interest in policies that might help respond to the growing problem of rural old‐age destitution. The focus of our analysis is on one of the most promising alternatives under consideration: universal non‐contributory old‐age pensions. This model has some limitations and it is not appropriate for all developing countries, but it would be of potential benefit to far more than the six that have already implemented variants of this approach. 相似文献
998.
Michael T. Molla Jennifer H. Madans Diane K. Wagener 《Population and development review》2004,30(4):625-646
This study examines mortality differentials and health disparities between educational groups within the 1998 adult population (ages 25 and older) in the United States. Mortality differentials are measured using average life expectancy and health disparities by expected years without activity limitation. The results indicate that for both sexes, higher education is associated with higher life expectancy. Those with higher levels of education also have higher life expectancy without activity limitation. Adults with higher education can also expect to enjoy a greater percentage of their expected lives free of any form of activity limitation. At each level of education, adult females have a higher level of activity limitation compared to adult males. At the same level of education, adult females expect to enjoy smaller percentages of their remaining lives free of activity limitation compared to adult males of the same age. 相似文献
999.
Timothy J. Loving Kathi L. Heffner Janice K. Kiecolt‐Glaser Ronald Glaser William B. Malarkey 《Journal of marriage and the family》2004,66(3):595-612
We investigated the impact of relative marital power on 72 newlywed couples’ endocrinological responses to marital conflict. Marital power was determined by comparing spouses’ reports of dependent love for one another. Less powerful spouses displayed elevated adrenocorticotropic hormone (ACTH) responses to a conflict discussion. Shared power appeared to have a beneficial effect on wives’ but not husbands’ ACTH responses. Spouses’ cortisol levels declined over time, except for wives who were less powerful and for husbands who shared power with their wives. Conflict behaviors did not differ as a function of this marital power index. These data suggest that relative levels of general emotional power in relationships may play an important role in spouses’ physiological responses to marital conflict. 相似文献
1000.
Whereas early threats are chosen before bargaining, late threats are determined after bargaining ended in conflict. Instead of exogenously imposing the timing of threats, these are derived endogenously as in indirect evolution or endogenous timing. Based on a duopoly market, we first derive the equilibrium for all possible constellations regarding the timing of threats. Our analysis surprisingly justifies the early timing of threats as suggested by Nash (1953). 相似文献