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971.
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   
972.
973.
This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.  相似文献   
974.
In the McGurk effect, perceptual identification of auditory speech syllables is influenced by simultaneous presentation of discrepant visible speech syllables. This effect has been found in subjects of different ages and with various native language backgrounds. But no McGurk tests have been conducted with prelinguistic infants. In the present series of experiments, 5-month-old English-exposed infants were tested for the McGurk effect. Infants were first gaze-habituated to an audiovisual /va/. Two different dishabituation stimuli were then presented: audio /ba/-visual /va/ (perceived by adults as /va/), and audio /da/-visual /va/ (perceived by adults as /da/). The infants showed generalization from the audiovisual /va/ to the audio /ba/-visual /va/ stimulus but not to the audio /da/-visual /va/ stimulus. Follow-up experiments revealed that these generalization differences were not due to a general preference for the audio /da/-visual /va/ stimulus or to the auditory similarity of /ba/ to /va/ relative to /da/. These results suggest that the infants were visually influenced in the same way as Englishspeaking adults are visually influenced.  相似文献   
975.
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   
976.
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   
977.
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   
978.
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   
979.
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   
980.
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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