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The present paper selectively reviews the literature which compares full-term and preterm infants' communication with their mothers in the first year of life. The review is focused not only on what differences are found between full-term and preterm infants, but also why such differences exist. Particular emphasis is placed on the importance of interpreting the findings in the light of the developmental phase of the infants, the heterogeneity of the preterm population and the situation in which communication is studied. Most studies were not designed to consider these issues in any detail. Differences with respect to these factors can be found between studies, however, which may have contributed to the often contradictory findings. Consequently, comparisons between these studies provide clues about the effects of these factors on communicative development. The ultimate goal of this review is to point to important directions for future research on early communication in preterm infants.  相似文献   
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We investigated the ability to match finger orientation to the direction of the axis of rotation in structure-from-motion displays. Preliminary experiments verified that subjects could accurately use the index finger to report direction. The remainder of the experiments studied the perception of the axis of rotation from full rotations of a group of discrete points, the profiles of a rotating ellipsoid, and two views of a group of discrete points. Subjects’ responses were analyzed by decomposing the pointing responses into their slant and tilt components. Overall, the results indicated that subjects were sensitive to both slant and tilt. However, when the axis of rotation was near the viewing direction, subjects had difficulty reporting tilt with profiles and two views and showed a large bias in their slant judgments with two views and full rotations. These results are not entirely consistent with theoretical predictions. The results, particularly for two views, suggest that additional constraints are used by humans in the recovery of structure from motion.  相似文献   
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The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.This research reported herein was performed pursuant to a contract (OE-2-10-071) with the United States Office of Education, Department of Health, Education and Welfare.  相似文献   
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The aim of this paper is twofold: (i) to introduce the framework of update semantics and to explain what kind of semantic phenomena may successfully be analysed in it: (ii) to give a detailed analysis of one such phenomenon: default reasoning.  相似文献   
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Mother–child concordance regarding children's somatic and emotional symptoms was assessed in children with recurrent abdominal pain (n = 88), emotional disorders (n = 51), and well children (n = 56). Children between 6 and 18 years of age and their mothers completed questionnaires assessing the children's somatic symptoms, functional disability, and depression. Mothers of children with recurrent abdominal pain reported more child somatic and depressive symptoms than did their children, and mothers of children with emotional disorders reported more child depressive symptoms than did their children. Higher levels of maternal distress were associated with greater mother-child discordance in the direction of mothers reporting more child symptoms than did their children. No significant child age or sex differences were found in concordance patterns.  相似文献   
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The current research advances a social dilemma analysis of commuting, examining the roles of preexisting personality differences in social value orientation (i.e., prosocial vs. proself orientation) and trust (i.e., a general belief in the honesty and cooperative intentions of others) in determining preferences for collectively desirable commuting options: preferences for commuting by public transportation (Study 1) and carpooling (Study 2). Consistent with predictions, both studies revealed that, relative to p of prosocials, preferences of proselfs were more strongly associated with beliefs about the relative efficiency of cars (i.e., an outcome affecting personal well-being). Also, greater preferences for collectively desirable actions were observed among prosocials with high trust—relative to prosocials with low trust and proselfs with high or low trust—providing support for the claim that 2 conditions (i.e., prosocial goals and trust in others) must be met to obtain collectively desirable commuting preferences.  相似文献   
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