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11.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
12.
A previous study (Tr?ster, 1989) showed that nonhandicapped persons preferred a physically handicapped interaction partner to a nonhandicapped partner in an attributionally unambiguous situation. In order to test whether this "sympathy effect of physical handicap" is based on tendencies of impression management, 48 female subjects had to choose to sit next to either a physically handicapped or nonhandicapped female interaction partner in order to view a film together. Attributional ambiguity was varied by either confounding the choice of an interaction partner with a second, socially acceptable alternative (attributionally ambiguous situation: a choice between two films) or not confounding it (attributionally unambiguous situation: no choice between films). Public responsibility was manipulated by informing the subjects about their freedom to choose where they wished to sit either in public (public responsibility) or in private (no public responsibility). The results supported the impression management hypothesis: The handicapped interaction partner (in a wheelchair) was only preferred when the subjects had to anticipate that observers would deduce a preference of the chosen partner from the subjects' choices because of the attributionally unambiguous situation and the public announcement of their freedom of choice. Results suggest that the nonhandicapped strive to exhibit positive and nondiscriminative behavior toward the handicapped in order to avoid creating a disadvantageous impression in an observer.  相似文献   
13.
In this paper three questions concerning quality of life in medicine and health care are analysed and discussed: the motives for measuring the quality of life, the methods used in assessing it, and the definition of the concept. The purposes of the study are to find an ethically acceptable motive for measuring the quality of life; to identify the methodological advantages and disadvantages of the most prevalent current methods of measurement; and to present an approach towards measuring and defining the quality of life which evades the difficulties encountered and discussed. The analysis comprises measurements both in the clinical situation concerning individual patients and in research concerning whole populations. Three motives are found for evaluating the quality of human life: allocation of scarce medical resources, facilitating clinical decision making, and assisting patients towards autonomous decision making. It is argued that the third alternative is the only one which does not evoke ethical problems. As for the methods of evaluation, several prevalent alternatives are presented, ranging from scales of physical performance to more subtle psychological questionnaires. Clinical questionnaires are found to fail to provide a scientific foundation for universally measuring the quality of life. Finally, the question of definition is tackled. The classical distinction between need-based and want-based theories of human happiness is presented and discussed. The view is introduced and defended that neither of these approaches can be universally preferred to the other. The difficulty with the need approach is that it denies the subjective aspects of human life; whereas the problem of the want approach is that it tends to ignore some of the objective realities of the human existence. In conclusion, it is argued that the choice of methods as well as definitions should be left to the competent patients themselves — who are entitled, if they so wish, to surrender the judgement to the medical personnel. Technical factors as well as the requirements of respect for autonomy and informed consent support this conclusion.  相似文献   
14.
Unreliable probabilities,risk taking,and decision making   总被引:7,自引:0,他引:7  
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15.
Agreement between adolescents, mothers, fathers, and teachers on adolescents' personality traits was investigated in a longitudinal study. The targets for personality ratings were the adolescents who participated in the European Youth Heart Study in Estonia. There were 593 participants in the first wave and 480 participants in the follow-up study 3 years later. Adolescents' self-reports as well as father, mother, and teacher ratings were collected using questionnaires to measure the five-factor model of personality. In both waves, inter-rater agreement was highest between mothers and fathers, was low to moderate for parent-self ratings, and was lowest for ratings between self and teacher, mother and teacher, and father and teacher. Test-retest correlations were moderate for parent and self-ratings but failed to reach statistical significance for three of the five teacher-rated traits, suggesting lower reliability of teacher ratings. Possible explanations for the low agreement between teachers and other judges are discussed.  相似文献   
16.
This review presents an analysis of articles in the journal “Psychotherapeut” during the years 2000 and 2001 with the focus on new efforts in the field of psychotherapeutic practice and research. The main topics of the journal are the presentation of new therapeutic approaches, some of them integrating different theoretical orientations, and the emphasis on the therapeutic relationship as a specific contribution to the process and the results of psychotherapy. In addition, this article presents a survey of the various subjects in psychotherapeutic research including a) the application and testing of new questionnaires to measure the effectiveness and the process of psychotherapy and b) research in the epidemiology of selected forms of stress, their consequences and lasting effects.  相似文献   
17.
Various attempts have been made to subdivide the corpus callosum (CC) into anatomically and functionally distinct subareas. A promising current approach is the use of factor analytic techniques in conjunction with traced MRI images. The traced images are divided into 99 percentile slices, where the widths of the percentile slices are used as variables that are entered into the analysis (Denenberg, Kertesz & Cowell, 1991). Studies that use this technique agree broadly between 6 and 7 factors, but available factor solutions contain inconsistencies and large gaps, which arise when many of the percentile slices do not load appreciably on any of the factors. The present study uses a larger number of brains (N = 184), all normalized, and some methodological refinements in the analysis of the traced MRI images of the CC. A stable 7 factor solution was found, and the factor structure for males and females was very similar.  相似文献   
18.
The aim of this investigation was to study the relationships between physical activity, motor ability, and school readiness in 6-yr.-old children. In total, 294 healthy children from Tartu were studied (161 boys and 133 girls). The physical activity of children was reported by parents and teachers using the questionnaire of Harro. The motor ability of children was evaluated using various tests from the Eurofit test battery as well as the 3-min. endurance shuttle run test. The Controlled Drawing Observation rest was used as a predictor of school readiness and development of mental abilities. Indoor physical activities predicted 19-25% of total variance in motor scores for these preschool children. Motor ability tests, which demand children's total attention and concentration, appear related to the chosen measures of school readiness.  相似文献   
19.
We examine how group members paradoxically refuse intergroup help where they might need it most: in the moral status domain. Based on the Sacred Value Protection Model (Tetlock, 2002), we predicted and found that group members felt stronger group-based anger and a stronger motivation to reaffirm their group's moral status when an outgroup was morally superior to them. Despite this moral motivation, however, we also predicted and found that group members more strongly refused intergroup help to improve their moral status vis-à-vis the morally superior outgroup (compared to an uninvolved outgroup). Consistent with the Social Identity model of Deindividuation Effects (Reicher, Spears, & Postmes, 1995), group members thus strategically refused intergroup help to defend their group identity. Supporting this interpretation, particularly highly identified group members were most likely to refuse intergroup help when they needed it most. We discuss theoretical and practical implications of our findings.  相似文献   
20.
Brain activity elicited by visually presented words was investigated using behavioral measures and current source densities calculated from high-resolution EEG recordings. Verbs referring to actions usually performed with different body parts were compared. Behavioral data indicated faster processing of verbs referring to actions performed with the face muscles and articulators (face-related words) compared to verbs referring to movements involving the lower half of the body (leg-related words). Significant topographical differences in brain activity elicited by verb types were found starting approximately 250 ms after word onset. Differences were seen at recording sites located over the motor strip and adjacent frontal cortex. At the vertex, close to the cortical representation of the leg, leg-related verbs (for example, to walk) produced strongest in-going currents, whereas for face-related verbs (for example, to talk) the most in-going activity was seen at more lateral electrodes placed over the left Sylvian fissure, close to the representation of the articulators. Thus, action words caused differential activation along the motor strip, with strongest in-going activity occurring close to the cortical representation of the body parts primarily used for carrying out the actions the verbs refer to. Topographically specific physiological signs of word processing started earlier for face-related words and lasted longer for verbs referring to leg movements. We conclude that verb types can differ in their processing speed and can elicit neurophysiological activity with different cortical topographies. These behavioral and physiological differences can be related to cognitive processes, in particular to lexical semantic access. Our results are consistent with associative theories postulating that words are organized in the brain as distributed cell assemblies whose cortical distributions reflect the words' meanings.  相似文献   
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