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851.
Are children as young as 2 years old able to interact in groups of three? The study applied the family triad model first introduced by Parke, Power, and Gottman (1979 ) to the case of peer interaction. In Experiment 1 , the model was refined for use in studies of peer interaction and applied to an existing dataset of 16 triads of newly acquainted 24‐month‐olds. In Experiment 2 , the triadic coding system was further refined and applied to 12 single‐sex triads of newly acquainted 2‐year‐olds. The findings demonstrated that 2‐year‐olds are capable of triadic interaction although the predominant interaction pattern in triads is still dyadic. Contrary to past reports, triadic interaction was more likely to occur when the children were not in conflict. Both girls and boys were capable of triadic interaction.  相似文献   
852.
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854.
In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSEij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), Fj (Partial F-test for the jth variable) and Fj(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSEIJ, FJ and FJ(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.  相似文献   
855.
Veenhoven (1994) contrasted hypotheses of whether happiness is a trait or state, concluding that it is a state variable. This article critiques the conceptual foundation of Veenhoven's paper, and examines technical deficiencies in his review of evidence. Based on previous findings and new analyses, we conclude that happiness has both traitlike and statelike properties, but that individual differences in happiness endure despite its situational reactivity, and explain greater variance than situational effects.  相似文献   
856.
The level of asbestos risk varies widely, with insulation workers facing risks many orders of magnitude greater than other groups, such as school children. After a period of regulatory neglect, asbestos risks are now among the mos stringently regulated risks, with costs per case of cancer prevented on the order of $100 million. Asbestos litigation triggered much of the public action against asbestos, as asbestos cases constituted the majority of all product liability cases in the federal courts from 1988 to 1991. The litigation costs have, however, been substantial, almost three times as great as the amounts transferred to asbestos disease victims. Risk communication potentially could promote efficient risk levels and victim compensation.  相似文献   
857.
The government, the market, and the problem of catastrophic loss   总被引:1,自引:0,他引:1  
This article addresses the comparative advantage of the government to the private property/casualty insurance industry for the provision of insurance coverage for catastrophic losses. That the government can play an important role as an insurer of societal losses has been a central public policy principle since at least the New Deal. In addition, our government typically automatically provides forms of specific relief following unusually severe or unexpected disasters, which itself can be viewed as a form of ex post insurance. This article argues that, for systemic reasons, the government is much less effective than the private property/casualty insurance market in providing coverage of losses generally, but especially of losses in contexts of catastrophes.  相似文献   
858.
Summary The evaluation of the performance of seasonal adjustment procedures is an issue of practical importance in view of the unobservable nature of the components. Looking at just one indicator when judging the overall quality of a procedure may be misleading, even though this is common practice when many series are involved. The main purpose of this paper is to compare the information content of different synthetic indicators with reference to the X-11-ARIMA procedure. Sixty-six different types of monthly seasonal series are generated and the seasonal component then extracted by carrying out X-11-ARIMA with standard options. The correlation between the pseudo-true error for each series and various synthetic indicators allows us to compare the latter's reliability, under both the hypotheses of minimum and maximum variance of the pseudo-true seasonal component. We show that the overall quality indexQ-the indicator most commonly adopted by users of the X-11-ARIMA-is always outperformed by the simpler diagnostics based on the stability of the estimates. In particular, the “sliding-spans” indicator, proposed by Findley et al. (1990) and included in the diagnostics of the new X-12 procedure, shows a much stronger correlation with the pseudo-true error in the seasonal adjustment. We also show that the total forecasting errors in the one-year-ahead extrapolation of the seasonal component have a good informative power and perform almost as well as the “sliding-spans” indicator.  相似文献   
859.
This two-part study applied an ecocultural perspective to socialization of daily and long-term goals in low-income Mexican-American and European-American families with children in third, fifth, and seventh grades. The first part of the study examined family members' participation and parents' socialization goals and guidance strategies for their children's daily household chores and homework activities. The second part of the study examined parents' long-term aspirations and guidance strategies for their children's educational, vocational, and moral development. For daily activities, results showed that in Mexican-American families both parents and siblings played important roles, whereas in European-American families parents were the primary socialization agents. As predicted, in both groups parents' expertise influenced their guidance strategies. Finally, Mexican-American and European-American parents differed in their relative endorsement of gender, relational, and self-reliance goals for household chores. For long-term goals, parents in both groups held high educational, vocational, and moral aspirations for their children. However, some parents of seventh-graders had lower educational and vocational aspirations than those of fifth- and third-graders. Although expertise consistently influenced Mexican-American parents' guidance strategies, the pattern for European-American parents was mixed. The discussion highlights between- and within-group differences in daily and long-term socialization practices with an emphasis on resources and vulnerabilities in the families.  相似文献   
860.
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