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41.
A characterization of stochastic independence in terms of association of random variables is given. The result is applied to yield a simple proof of the Sattath-Tversky inequality without continuity assumptions.  相似文献   
42.
In this paper a propositional logic of viewpoints is presented. The language of this logic consists of the usual modal operatorsL (of necessity) andM (of possibility) as well as of two new operatorsA andR. The intuitive interpretations ofA andR are “from all viewpoints” and “from some viewpoint”, respectively. Semantically the language is interpreted by using Kripke models augmented with sets of “viewpoints” and with a new alternativeness relation for the operatorA. Truth values of formulas are evaluated with respect to a world and a viewpoint. Various axiomatizations of the logic of viewpoints are presented and proved complete. Finally, some applications are given.  相似文献   
43.
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   
44.
Forty-five patients with unilateral demarcated vascular lesions in the basal ganglia, the thalamus and the deep white matter were investigated with an "aphasia battery." Patients with basal ganglia lesions performed worse than both other groups in tests of articulation, syntax, and lexical functions. The deficit of patients with basal ganglia lesions on all expressive language modalities was lateralized to the left hemisphere. Patients with left thalamic lesions showed impairments of speech fluency and in the Token Test. Patients with white matter lesions alone showed no effect of laterality in tests of language functions. The results are discussed on the basis of a recent theory of the participation of the deep nuclei in language processing.  相似文献   
45.
The following comparisons between Freud's and Piaget's concepts are proposed: eros drive = constructive assimilation = direction toward the object in the sense of love for newness and otherness; death drive = constrictive assimilation = direction away from or destruction of the object out of fear for self to preserve the system. Eros and assimilation drive combine in the developing object and symbol formation to transform personal relations and knowledge. These psychological theories are further confirmed by evolutionary considerations about human social relations and by Macmurray's philosophy of personal relations as the primary function of reason.  相似文献   
46.
This study aimed to clarify how manifestations and acquisition relate to diagnostic categories of dental fear in a population of self-referred dental fear patients, since diagnostic criteria specifically related to dental fear have not been validated. DSM III-R diagnostic criteria for phobias were used to compare with four existing dental fear diagnostic categories, referred to as the Seattle system. Subjects were 208 persons with dental fear who were telephone interviewed, of whom a subsample of 155 responded to a mailed Dental Anxiety Scale (DAS), State-Trait Anxiety Inventory and a modified FSS-II Geer Fear Scale (GFS). Personal interviews and a Dental Beliefs Scale of perceived trust and social interaction with dentists were also used to evaluate a subsample of 80 patients selected by sex and high dental fear. Results showed that the majority of the 80 patients (66%), suffered from social embarrassment about their dental fear problem and their inability to do something about it. The largest cause of their fear (84%) was reported to be traumatic dental experiences, especially in childhood (70%). A minority of patients (16%) could not isolate traumatic experiences and had a history of general fearfulness or anxiety. Analysis of GFS data for the 155 subjects showed that fear of snakes and injuries were highest among women; heights and injections among men. Fear of blood was rarely reported. Spearman correlations between GFS individual items and DAS scores indicated functional independence between dental fear and common fears such as blood, injections and enclosures in most cases. Only in specific types of dental fear did these results support Rachman and Lopatka's contention that fears are thought to summate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
47.
ABSTRACT The aim of this study was to test whether the concept of an altruistic personality was valid for first aiders who intervened to help the victims of a traffic accident. We derived a number of relevant personality variables that should be related to the willingness to administer first aid. These include locus of control, social responsibility, belief in a just world, empathy, and instrumentality. We obtained data from proven first aiders who had intervened after a traffic accident. Thirty-four of these first aiders were matched to respondents from a subject pool on the basis of sex, age, and socioeconomic status. In addition, the willingness of these respondents to offer help after a traffic accident was taken into account. Only people who indicated that they had witnessed an accident and had not helped were included in the control group. Multivariate analyses of variance and covariance indicated that proven first aiders deviated from the control group on several dimensions: They described themselves as more internal, believed more in a just world, and emphasized more social responsibility and empathy.  相似文献   
48.
49.
Summary In an experiment modelled upon the classical paradigm on release from proactive interference (PI), subjects were required to remember series of actions they had performed (e.g., roll the ball, fold the paper). The objects involved in these subject-performed tasks (SPTs) served as a basis for build-up and release of PI. The objects used in the first few trials of the experiment belonged to the same class (e.g., parts of the body), causing a build up of PI. A shift to a different class of objects (e.g., kitchen utensils) along four different dimensions (taxonomic category, weight, color, and size) was introduced to cause a release of PI. On the basis of PI-release experiments with words it was expected that shifts in taxonomic category would result in a greater release than shifts within any of the physical dimensions. However, the results revealed that the amount of PI release was, in general, larger than expected, and essentially the same for all four dimensions investigated. The results are discussed in terms of the nature of the memory representation of SPTs, and with regard to possible processing differences between SPTs and verbal information. In addition, methodological suggestions for furthering the understanding of the encoding and storage of action events are advanced.  相似文献   
50.
The pioneering work of the authors of the Type A personality concept has now been shown to be seriously flawed, with only the traits of anger, aggression, and hostility remaining as risk factors for coronary heart disease (CHD). There is now evidence for a much stronger relationship between CHD and personality involving a rather different set of concepts and theories. The evidence for such a relationship is summarized, and a causal link suggested. It is also shown that the CHD-prone type of behaviour can be changed by behaviour therapy, decreasing considerably the risk of dying from CHD.  相似文献   
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