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271.
H H?fner 《Psychiatrie, Neurologie, und medizinische Psychologie》1989,41(8):449-475
Since more than one century suicides have been registered in national statistics of death causes. They thus furnish one of the few parameters of psychiatrically relevant behaviour by means of which trends, cohort, age-group and period effects can be studied over longer periods. Since the second half of last century, the suicide rates for Swiss males--similar to those found in England and Wales--show a decrease in consecutive birth cohorts up to males born in the decade 1930-1940, and a continued decline in the total trend until about World War II. From then on the suicide rates of males in consecutive birth cohorts have been slowly increasing in the majority of European and North American countries--but not so in Sweden. Opposite to this, the predominantly low rates for females display little change. Further to the considerable differences between nations and the predominance of suicides committed by females in some Asian countries and Cuba, the changes indicate the significance of cultural and economic environmental factors. Typical period effects are mainly the result of changes in conception and conditions of life. In attempted suicide they proceed in a more sensitive and more rapid way and are about ten times higher. Such a period effect showing increases by about 300% in younger age-groups followed by a decline, attaining its peak about 1976, was ascertained in large cities of the Federal Republic of Germany. By the example of the effects of a television serial, the study of causal processes turning collective environmental factors into individual suicidal behaviour, proved that regularities are effective in learning by a process of modelling. Besides, the epidemiological data give essential hints how to treat suicidal behaviour. 相似文献
272.
The developmental change in subjective probability during adolescence, an important period for establishing the probability concept, was investigated. 75 Japanese adolescents, from 12 to 23 yr. of age, were asked to make probability judgments for a lottery under 15 conditions. Analysis showed that with increase in age their subjective probability came closer to the objective probability. Discussion of these results took into consideration recent studies on the development of the concept of probability. 相似文献
273.
To assess temporal variations in the perception of "phasic" heat pain stimuli a psychophysical tracking procedure was developed that enables repeated assessment of the pain threshold at short intervals. This "double-tracking" procedure produces two tracking curves simultaneously, one that approaches the pain threshold gradually from above, the other from below. The threshold for phasic heat pain was measured in 80 tracking trials with stimuli at temperatures near the pain threshold. Concurrently, the threshold for "tonic" heat pain was determined after every 20 tracking trials with a stimulus adjustment procedure. Eleven healthy subjects (age: 26.4 yr. +/- 6.0) participated in 2 sessions each. Phasic stimulation near the pain threshold did not produce any trends in either of the two threshold measures. Hence there was no long-term adaptation or sensitization. However, there were random variations (random walks) in the tracking curves, which we interpret as resulting from a stochastic relationship between stimulus and sensation. In agreement with other reports, discrimination seemed to be better at painful than at nonpainful temperatures. 相似文献
274.
H N Levinson 《Perceptual and motor skills》1989,68(2):471-484
As prior studies indicated abnormal cerebellar-vestibular-based sensorimotor mechanisms and neurological and ENG diagnostic parameters in anxiety disorders and because ocular fixation and sequential scanning are cerebellar-vestibular-modulated, it appeared reasonable to measure these and related ocular functions in matched samples of anxiety-disordered and control subjects. In this study, the optokinetically-determined fixation, sequential scanning, and perceptual span capacities obtained by means of a newly revised blurring-speed method were significantly lower or impaired in 70 anxiety-disordered patients vs 70 controls. Such data supported further the hypothesis that there may be cerebellar-vestibular predispositions to anxiety disorders and the optokinetically-based tracking method may prove useful in separating a diverse array of CV-determined or related anxiety symptoms from those of other origins. However, independent validation as well as additional studies of anxiety disorders using larger samples vs random or "normal" controls are required before conclusions are justified. 相似文献
275.
276.
H Kock 《Archiv für Psychologie》1989,141(3):175-193
A model of linkage in text processing is proposed: An external proposition and an inference belonging to one frame are superimposed to constitute understanding. A text containing four academic subjects was presented orally to students who recalled it in writing. After transforming the recalls into propositions they are entered into a nonmetric multidimensional scaling to yield a text space. The subjects' interest choices among items of the four aspects are scaled to render an interest space. The decomposition ob both as subspaces of a common space yields an angle as their overall similarity and indicates the degree of predictability from interests. As the aggregate of inferences shows directedness, correlated with volitional-motivational orientation, and inference base is assumed to intervene. It is concluded that recipients try to superimpose and thereby construct a primary stage of processing. This allows for a very general algorithm of parallel information processing (holographic thesis), perhaps constructing the properties we are used to. Motivated perception, knowledge influence, schema-directedness and contribution to coherence are rivalled out as an explanation of this process. 相似文献
277.
The development of problem-solving skills from novices to advanced subjects in dependence of the competence level of the opponent is examined in a two-person zero-sum game (Othello). In a repeated-measurement design 18 Ss. (6 Ss in 3 groups) played 10 games against one of three opponent-strategies (implemented on a computer): one "expertlike" strategy, which uses domain specific knowledge and local heuristics (minimax-algorithm with alpha-beta pruning); one "novicelike" strategy, in which global, domain independent problem solving strategies (means-ends analysis, goal-reduction) are implemented; and one strategy, which contradicts the supposed heuristics of the novices, but which results in a "weak" performance (minimization in move-selection). Contrary to our assumptions no significant effects of experience could be verified (win versus loss during single runs). An experience dependent differentiation of global problem solving strategies could not be shown for any of the groups. Neither could a general improving effect of the model for acquiring local, task specific heuristics be proved. 相似文献
278.
Peter Turney 《Synthese》1989,79(3):515-542
The logic of scientific discovery is now a concern of computer scientists, as well as philosophers. In the computational approach to inductive inference, theories are treated as algorithms (computer programs), and the goal is to find the simplest algorithm that can generate the given data. Both computer scientists and philosophers want a measure of simplicity, such that simple theories are more likely to be true than complex theories. I attempt to provide such a measure here. I define a measure of simplicity for directed graphs, inspired by Herbert Simon's work. Many structures, including algorithms, can be naturally modelled by directed graphs. Furthermore, I adapt an argument of Simon's to show that simple directed graphs are more stable and more resistant to damage than complex directed graphs. Thus we have a reason for pursuing simplicity, other than purely economical reasons.This paper is based on part of my doctoral dissertation. Thanks to my thesis supervisor Professor Alasdair Urquhart for his encouragement, constructive criticism, and for directing me to several relevant articles; to my advisor, Professor Ian Hacking, for reminding me to concentrate on results that might have some application in the real world; to Professor Eric Mendelsohn for checking my use of graph theory; and to my friend Wendy Brandts for sharing her ideas on a closely related problem.Thanks to my friends and family (the latter being a (proper) subset of the former, and both including Dr. Louise Linney, of course) for ongoing support in my scholastic endeavors.Thanks to the Social Sciences and Humanities Research Council for financial assistance. (Awards 452-86-5885 and 453-87-0513.) Thanks to the University of Toronto for financial assistance. 相似文献
279.
H Rübeling S Meckfessel 《Zeitschrift für experimentelle und angewandte Psychologie》1989,36(3):476-493
The present 2 x 2 study deals with the influence of controllability and predictability of an aversive noise stimulus on a subsequent learning task. Eighty-four subjects participated in two experiments. In correspondence with the concept of learned helplessness, controllability was shown to be the dominant factor in the first experiment. In the second experiment, a modified test task was used in which both factors were shown to act in specific ways: The main influence of controllability is upon response measures (latency, omission), whereas unpredictability retardates learning of new predictive connections. The results are discussed in terms of contingency learning. 相似文献
280.
The hypothesis testing skills of undergraduates were measured in two tasks: the 2-4-6 rule discovery task in which students generate and assess hypotheses, and a hypothesis evaluation task, which requires only the assessment of hypotheses. The results of Experiments 1 and 2 show that the students consistently employed a disconfirmation strategy when assessing hypotheses, but employed a counterfactual inference strategy when they also were required to generate the hypotheses. The results of Experiment 3 suggest that the selection of the hypothesis testing strategy reflected a balance between the logical requirements of the task and the desirability of possible outcomes. Taken together, the findings support a more consistent picture of human rationality across tasks, and suggest alternatives to accounts of confirmation bias. 相似文献