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991.
Nonparametric regression techniques, which estimate functions directly from noisy data rather than relying on specific parametric models, now play a central role in statistical analysis. We can improve the efficiency and other aspects of a nonparametric curve estimate by using prior knowledge about general features of the curve in the smoothing process. Spline smoothing is extended in this paper to express this prior knowledge in the form of a linear differential operator that annihilates a specified parametric model for the data. Roughness in the fitted function is defined in terms of the integrated square of this operator applied to the fitted function. A fastO(n) algorithm is outlined for this smart smoothing process. Illustrations are provided of where this technique proves useful.  相似文献   
992.
Germund Hesslow has argued that concepts of health and disease serve no important scientific, clinical, or ethical function. However, this conclusion depends upon the particular concept of disease he espouses; namely, on Boorse's functional notion. The fact/value split embodied in the functional notion of disease leads to a sharp split between the “science” of medicine and bioethics, making the philosophy of medicine irrelevant for both. By placing this disease concept in the broader context of medical history, I shall show that it does capture an essential part of modern medical ideology. However, it is also a self-contradictory notion. By making explicit the value desiderata of medical nosologies, a reconfiguration of the relation between medicine, bioethics, and the philosophy of medicine is initiated. This, in turn, will involve a recovery of the caring dimensions of medicine, and thus a more humane practice.  相似文献   
993.
“二十一世纪的心理学”的论题是当今许多科学家感兴趣的.这种预测是一种想象与现实相结合的尝试。审视过去和现在.心理学未来的雏形的基础可能是行为与脑的关系及其与生命其它属性之间的相互作用。  相似文献   
994.
Multidimensional scaling (MDS) was used to compare perceptual maps for 10 synthetic English vowels in humans and Old World monkeys (Macaca fuscata andCercopithecus albogularis). Subjects discriminated among the vowels using a repeating background procedure, and reaction times were submitted to an MDS analysis to derive measures of perceived similarity. The dimensions that emerged related to the frequencies of the first(F1), second(F2), and third(F3) formants. Human data indicated a good match to previous MDS studies using rating procedures or confusion matrices: The dominant dimension mapped onto vowelF2, the phonetically most important formant, and the second and third dimensions mapped ontoF1 andF3, respectively.For monkeys, equal weightings occurred forF1 andF2, andF3 was not clearly represented. Monkey sensitivity to the formants appeared to relate to formant amplitudes. If monkeys are giving an accurate representation of the psychoacoustic relations among the formants, then our human results suggest that species-specific mechanisms, reflecting the salience of the phonetic feature of advancement, may contribute to vowel coding in humans.  相似文献   
995.
In a previous study of two-choice reactions, pairings of spatial stimuli with bimanual presses made on a keyboard and verbal stimuli with unimanual aimed movements made on a display screen showed higher set-level compatibility than the opposite pairings; element-level compatibility (i.e., mapping) effects were also larger for the conditions with high set-level compatibility than for those whose set-level compatibility was low. In the 4 experiments described here, the relevant factors were isolated, allowing the determinants of those compatibility differences to be evaluated in more detail. Forty-eight students participated in Experiment 1, and 24 each in Experiments 2, 3, and 4. The primary determinant of the set-level compatibility variation was whether the response alternatives involved 1 or 2 effectors, but the differences in element-level compatibility effects were determined primarily by the distinction between responding on the screen as opposed to on the keyboard. Implications for models of stimulus-response compatibility are examined.  相似文献   
996.
We argue that negotiators' fixed-sum perceptions are caused by the same judgment process that creates false consensus. Bargainers' reliance on their own preferences as a cue to others' preferences leads them to anticipate a fixed-sum conflict. When presented with stereotypic cues, subjects in a negotiating experiment anticipated the variable-sum nature of the task and subsequently realized highly efficient settlements extremely quickly. Surprisingly, even when the party's preferences were unrepresentative of the stereotype, agreements were no less efficient than in the absence of the cue. The implications of these findings for bargaining research and practice are discussed.  相似文献   
997.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
998.
ABSTRACT It has been hypothesized that individuals who are high on the attribute of self-criticism are particularly vulnerable to failure stress. To test this hypothesis, we examined the relationship between self-criticism and changes in plasma homovanillic acid (HVA; the metabolite of dopamine) and emotion during exposure to an induced-failure task. Participants consisted of 21 women. Plasma HVA and emotion were assessed at three time points: baseline (T1), during stress exposure (T2), and 40 minutes after cessation of the stressor (T3). We found that self-criticism was significantly and positively related to changes in plasma HVA during stress exposure. In addition, the personality attribute was significantly and positively related to subjective ratings of stress and changes in scores on the Confusion-Bewilderment scale of the Profile of Mood States during the task. To our knowledge, this is the first study to report that self-criticism is related to stress-induced changes in biochemistry.  相似文献   
999.
ABSTRACT College students who had yet to marry and begin a family were asked about their desire to have children and their beliefs and expectations about themselves as parents (Study 1) and the characteristics of their prospective children (Study 2). Persons with more avoidant and anxious-ambivalent models of close adult relationships harbored more negative models of parent-hood and parent-child relationships. These findings indicate that working models of parenting and parent-child relationships form well before marriage and the birth of children and that these models are systematically associated with attachment styles in adult relationships. The findings also suggest ways in which insecure attachments between child and parent may be influenced by the caregiver's models of parenting and parent-child relationships.  相似文献   
1000.
In the present study, we examined the effects of perceived overqualification on health and the moderating effect of emotional support. Exploratory and confirmatory factor analyses found 2 indicators of perceived overqualification: "mismatch" and "no-grow." Perceived mismatch had a significant negative effect on health but perceived no-grow did not. The main effect revealed that the greater the perceived emotional support, the greater the health. The significant interaction of perceived emotional support and mismatch, and perceived emotional support and no-grow on health indicates that the negative effects of overqualification on health was greater for those perceiving low emotional support than for those perceiving high emotional support. The significance of social support in illuminating the relationship between perceived overqualification and health are discussed.  相似文献   
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