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51.
52.
We examine how attention to animacy information may contribute to children's developing knowledge of language. This research extends beyond prior research in that children were shown dynamic events with novel entities, and were asked not only to comprehend sentences but to use sentence structure to infer the meaning of a new word. In a 4 × 3 design, animacy status (e.g., animate agent, inanimate patient) and labeling syntax (agent, patient, nonlabel control) were varied. Across most events, 2 1/2‐year‐old participants responded as if they expected animate entities to be named. However, in a prototypical (animate agent‐inanimate patient) event condition, children responded differentially across different syntactic structures. Thus, the clearest evidence for attention to syntactic cues was found in the prototypical event condition. These results suggest that young children attend to the animacy status of unfamiliar entities, that they have expectations about animacy relations in events, and that these expectations support emerging syntactic knowledge. 相似文献
53.
54.
Donald B. Rubin 《Scandinavian Journal of Statistics》2004,31(2):161-170
Abstract. The use of the concept of ‘direct’ versus ‘indirect’ causal effects is common, not only in statistics but also in many areas of social and economic sciences. The related terms of ‘biomarkers’ and ‘surrogates’ are common in pharmacological and biomedical sciences. Sometimes this concept is represented by graphical displays of various kinds. The view here is that there is a great deal of imprecise discussion surrounding this topic and, moreover, that the most straightforward way to clarify the situation is by using potential outcomes to define causal effects. In particular, I suggest that the use of principal stratification is key to understanding the meaning of direct and indirect causal effects. A current study of anthrax vaccine will be used to illustrate ideas. 相似文献
55.
Banks winners in tournaments are difficult to recognize 总被引:1,自引:0,他引:1
Gerhard J. Woeginger 《Social Choice and Welfare》2003,20(3):523-528
Given a tournament T, a Banks winner of T is the top vertex of any maximal (with respect to inclusion) transitive subtournament of T. In this technical note, we show that the problem of deciding whether some fixed vertex v is a Banks winner for T is NP-complete.
Received: 22 February 2002/Accepted: 20 June 2002
Supported by the START program Y43-MAT of the Austrian Ministry of Science.
I would like to thank two thank the referees for a careful reading of the paper, for helpful remarks, and for many suggestions
how to improve the presentation. 相似文献
56.
Abstract Using data from a national survey in Bolivia and from a regional sample of poor communities in two regions of Bolivia, we model the effects of community conditions, household characteristics, and social relations on child health as measured by child mortality and stunted growth. Based on national data, children in rural areas are twice as likely to die before the age of two than are children in large cities, and about one‐third of the children in rural areas are stunted. Including measures of community, household, and maternal characteristics accounts for at least two‐thirds of the urban/rural difference in child health. We conclude that expansion of health services, improvements in household and community sanitation, and socioeco‐nomic development are all needed to overcome the rural disadvantage in child health. 相似文献
57.
Gayane Novikova 《Transition Studies Review》2004,11(3):213-223
The collapse of the USSR was accompanied by transformation of the South Caucasian latent ethnopolitical conflicts into local wars. Today the situation in the area of the conflicts is “neither war, nor peace”. Three unresolved conflicts of the South Caucasus can be considered as one of the most serious obstacles for establishing a regional security system.The article gives the general characteristics of these conflicts, the trends of their development, taking into account the time factor, and analyzes the behavioral models of the main players – de jure recognized and unrecognized de facto states of the South Caucasus. The basic objective of the main players should be to keep the situation on a level preventing the resumption of the armed conflicts. The attempts of forced resolution of the conflicts are fraught with destabilization of the situation not only in the area of any of these conflicts but in the whole region. 相似文献
58.
Lu Lin 《Statistical Papers》2004,45(4):529-544
The quasi-score function, as defined by Wedderburn (1974) and McCullagh (1983) and so on, is a linear function of observations.
The generalized quasi-score function introduced in this paper is a linear function of some unbiased basis functions, where
the unbiased basis functions may be some linear functions of the observations or not, and can be easily constructed by the
meaning of the parameters such as mean and median and so on. The generalized quasi-likelihood estimate obtained by such a
generalized quasi-score function is consistent and has an asymptotically normal distribution. As a result, the optimum generalized
quasi-score is obtained and a method to construct the optimum unbiased basis function is introduced. In order to construct
the potential function, a conservative generalized estimating function is defined. By conservative, a potential function for
the projected score has many properties of a log-likelihood function. Finally, some examples are given to illustrate the theoretical
results.
This paper is supported by NNSF project (10371059) of China and Youth Teacher Foundation of Nankai University. 相似文献
59.
Starting with its early twentieth century origins, the development of Labor Economics is traced to the present. We describe
an intellectual revolution in which an earlier tra-dition that focused primarily on the institution of the labor union has
been replaced by a perspective that emphasizes the various roles played by labor markets in an eco-nomic system. That earlier
tradition contained very significant ideological elements, whereas its successor deals much more with the world of ideas.
In the course of the debate, which still continues, ideas triumphed over ideology and created modern Labor Economics. 相似文献
60.