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941.
Jürgen Humburg 《Topoi》1986,5(1):39-50
The aim of my book is to explain the content of the different notions of probability.Based on a concept of logical probability, which is modified as compared with Carnap, we succeed by means of the mathematical results of de Finetti in defining the concept of statistical probability.The starting point is the fundamental concept that certain phenomena are of the same kind, that certain occurrences can be repeated, that certain experiments are identical. We introduce for this idea the notion: concept K of similarity. From concept K of similarity we derive logically some probability-theoretic conclusions:If the events E() are similar —of the same kind - on the basis of such a concept K, it holds good that intersections of n of these events are equiprobable on the basis of K; in formulae: E(1)...E(
n
K
E('1)...E('
n
,
i
j
,'
j
'
j
for ij
On the basis of some further axioms a partial comparative probability structure results from K, which forms the starting point of our further investigations and which we call logical probability on the basis of K.We investigate a metrisation of this partial comparative structure, i.e. normed -additive functions m
K, which are compatible with this structure; we call these functions m
K
measure-functions in relation to K.The measure-functions may be interpreted as subjective probabilities of individuals, who accept the concept K.Now it holds good: For each measure-function there exists with measure one the limit of relative frequencies in a sequence of the E().In such an event, where all measure-functions coincide, we speak of a quantitative logical probability, which is the common measure of this event. In formulae we have: l
K
(h
n
lim h
n
)=1 in words: There is the quantitative logical probability one that the limit of the relative frequencies exists. Another way of saying this is that the event
* (hn lim h
n) is a maximal element in the comparative structure resulting from K.Therefore we are entitled to introduce this limit and call it statistical probability P.With the aid of the measure-functions it is possible to calculate the velocity of this convergence. The analog of the Bernoulli inequation holds true: m
K
(¦h
n
–P¦)1–1/4n2.It is further possible in the work to obtain relationships for the concept of statistical independence which are expressed in terms of the comparative probability.The theory has a special significance for quantum mechanics: The similarity of the phenomena in the domain of quantum mechanics explains the statistical behaviour of the phenomena.The usual mathematical statistics are explained in my book. But it seems more expedient on the basis of this new theory to use besides the notion of statistical probability also the notion of logical probability; the notion of subjective probability has only a heuristic function in my system.The following dualism is to be noted: The statistical behaviour of similar phenomena may be described on the one hand according to the model of the classical probability theory by means of a figure called statistical probability, on the other hand we may express all formulae by means of a function, called statistical probability function. This function is defined as the limit of the relative frequencies depending on the respective state of the universe. The statistical probability function is the primary notion, the notion of statistical probability is derived from it; it is defined as the value of the statistical probability function for the true unknown state of the universe.As far as the Hume problem, the problem of inductive inference, is concerned, the book seems to give an example of how to solve it.The developed notions such as concept, measure-function, logical probability, etc. seem to be important beyond the concept of similarity.The present work represents a summary of my book Grundzüge zu einem neuen Aufbau der Wahrscheinlich-keitstheorie [5], For this reason, I have frequently dispensed with providing proof and in this connection refer the interested reader to my book. 相似文献
942.
Occupational and life stress and the family: conceptual frameworks and research findings 总被引:1,自引:0,他引:1
Ronald J Burke 《Psychologie appliquee》1986,35(3):347-368
This article has two objectives: (1) to put research on work and family into a context or setting; and (2) to present recent findings from an ongoing research programme we began several years ago into the ways in which work experiences, and more general life experiences, influence individual well-being and family functioning. 相似文献
943.
The relationship between eye movements and spatial attention 总被引:8,自引:0,他引:8
Martin Shepherd John M. Findlay Robert J. Hockey 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》1986,38(3):475-491
Most previous studies of the attentional consequences of making saccadic eye movements have used peripheral stimuli to elicit eye movements. It is argued that in the light of evidence showing automatic “capture” of attention by peripheral stimuli, these experiments do not distinguish between attentional effects due to peripheral stimuli and those due to eye movements. In the present study, spatial attention was manipulated by varying the probability that peripheral probe stimuli would appear in different positions, while saccades were directed by a central arrow, enabling the effects of attention and eye movements to be separated. The results showed that the time to react to a peripheral stimulus could be shortened both by advance knowledge of its likely position and, separately, by preparing to make a saccade to that position. When the saccade was directed away from the most likely position of the probe, the targets for attention and eye movements were on opposite sides of the display. In this condition, the effects of preparing to make a saccade proved to be stronger than the effects of attentional allocation until well after the saccade had finished, suggesting that making a saccade necessarily involves the allocation of attention to the target position. The effects of probe stimuli on saccade latencies were also examined: probe stimuli that appeared before the saccade shortened saccade latencies if they appeared at the saccade target, and lengthened saccade latencies if they appeared on the opposite side of fixation. These facilitatory and inhibitory effects were shown to occur at different stages of saccade preparation and suggest that attention plays an important role in the generation of voluntary eye movements. The results of this study indicate that while it is possible to make attention movements without making corresponding eye movements, it is not possible to make an eye movement (in the absence of peripheral stimulation) without making a corresponding shift in the focus of attention. 相似文献
944.
T O Nelson R J Leonesio R S Landwehr L Narens 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(2):279-287
Distinctions are drawn between different predictors of an individual's memory performance, with emphasis on the notion of privileged access to idiosyncratic knowledge. Research is reported in which undergraduates attempted to recall the answers to general-information questions, then made feeling-of-knowing judgments on nonrecalled items, and subsequently had a criterion test (relearning, perceptual identification, or one of two versions of recognition). For predicting an individual's criterion performance, the individual's own feeling-of-knowing predictions were intermediate between two kinds of normative predictions: The individual's feeling-of-knowing predictions were more accurate than predictions derived from normative feeling-of-knowing ratings but were less accurate than predictions derived from base-rate item difficulty (normative probabilities of correct recall). Subsidiary analyses showed that factors other than unreliability are responsible for the partial inaccuracy of the individual's feeling of knowing. Ramifications are discussed for possible ways to improve the accuracy of an individual's feeling-of-knowing predictions. 相似文献
945.
Cue depreciation: when word fragment completion is undermined by prior exposure to lesser fragments 总被引:3,自引:0,他引:3
Z F Peynircio?lu M J Watkins 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(3):426-431
The ability to think of a previously studied item has often been shown to be impaired when, in one way or another, the extraitem context is changed from study to test. In a series of five experiments, such impairment is induced in a somewhat different way. A fragment (e.g. r-i--rop) of a just-studied word (raindrop) is shown to be less readily completed if it is presented bit by bit (r------p, r----r-p, r-i--r-p, r-i--rop) rather than all at once (Experiments 1, 3, 4, and 5). No such effect is found if the word has not been studied beforehand (Experiments 2, 3, 4, and 5). This pattern of results occurs even when fragments of studied and nonstudied words occur in the same test and under conditions in which subjects cannot tell whether a given fragment is of a studied or nonstudied word (Experiments 4 and 5). In addition, for words that have been studied beforehand, the impairment is shown to increase systematically with the number of steps involved in the presentation of the word fragment (Experiment 3) and also to persist when the time allowed for completion of the final version of the fragment is increased from 4 s to a full minute (Experiment 5). 相似文献
946.
An assessment of decision-making as a possible factor in the age-related loss of contrast sensitivity 总被引:1,自引:0,他引:1
The possibility that changes in decision-making may contribute to the age-related decline in contrast sensitivity has been investigated in nineteen young subjects (ages 21-38 years) and twenty-seven old subjects (ages 55-92 years). A signal detection paradigm was employed in which the detection of stationary sinusoidal grating patterns was measured at 3 and 15 cycles deg-1 for a range of contrasts which were psychophysically equivalent for each subject. A decline in contrast sensitivity with age at the spatial frequencies studied was confirmed for contrast thresholds obtained both by the ascending method and from the 50% hit rate for detection of the grating pattern. The criterion adopted for decision-making, expressed as both beta and percentage bias, did not change significantly between young and old subjects at 15 cycles deg-1. At 3 cycles deg-1, criterion beta did not change significantly at X0.8, X1.0, or X1.2 contrast threshold, but at contrast giving 50% hit rate there was a significant increase with age. The percentage bias increased significantly at contrast threshold but not at 50% hit rate. It is inferred from the results that the loss of contrast sensitivity was not accountable in terms of the adoption of a more conservative criterion by older subjects. Hence visual loss in ageing is attributed to changes within the visual pathway rather than within higher decision-making centres. 相似文献
947.
Cognitive, motivational, social, and environmental influences on children's food choices 总被引:2,自引:0,他引:2
This study tested the applicability of a cognitive-motivational model of health behavior to children's food choices. A sample of 107 elementary schoolchildren provided ratings of 15 foods in terms of possible choice criteria (e.g., how tasty or healthful specific foods were) and social or environmental influences (e.g., whether foods were eaten by friends or were easy to get). Several measures of food consumption were taken, and cognitive-developmental level was assessed. Within-person correlations were calculated between food choices and each choice criterion and social/environmental factor. These "correlational indices" of influences on food choice subsequently were used to identify five distinct subgroups in the sample. Children at the operational level of cognitive development tended to be in one of three groups characterized by health orientation in food choice, taste orientation, or multiple-motive orientation. Dietary quality was poorest in the taste-oriented group. Children at the preoperational level tended to have one of two undifferentiated patterns of values across the correlational indices. Results provide evidence of: the viability of cognitive-motivational models to explain children's food choices, the promise of within-person research methodology, and the potential for enhanced health behavior-change programs by use of population segmentation and tailored interventions. 相似文献
948.
The authors summarize trends for several indicators of student career development collected in 1973 (when career education and career planning programs began to receive renewed emphasis) and again in 1983. The indicators, obtained for nationally representative samples of junior and senior high school students (N = 18,129 in 1973 and 15,432 in 1983), included career-related concerns, career planning involvement, and reactions to career planning services. Among the major trends was a 32% increase in the proportion of 11th graders who reported receiving “some” or “a lot” of career planning help from their schools. Moreover, the proportion of students involved in typical career exploration activities increased significantly over the 10 years of the study. In general, the 10-year trends indicate that schools are having a greater impact on student career development than they were in 1973. 相似文献
949.
Dating experiences, especially the type or stage of dating, have consistently been found to be related to premarital sexual behavior. Findings regarding the age at 1st date and sexual behavior have been less consistent. This paper examined the age at which dating began and the type of dating relationship as correlates of premarital sexual attitudes and behavior among mid-teen adolescents. The analyses were based on a sample of high school students (n=836), most of whom were between the ages of 15 and 18 when the surveys were conducted. Early dating, especially early steady dating, was related to permissive attitudes and to premarital sexual experience among both males and females. The relationship between early dating and intercourse experience was particulary strong among Mormons, a religious group which has institutionalized age 16 as the legitimate age to begin dating. 相似文献
950.
J K O'Hanlon B D Sachs 《Journal of comparative psychology (Washington, D.C. : 1983)》1986,100(2):178-187
Three experiments with rats (Rattus norvegicus) were conducted to examine the roles of the male's penile spines and penile cups (flaring of the distal glans) in the induction of luteal activity in the female, and in the removal of copulatory plugs from the vaginal tract. The results of Experiment 1 revealed no role for the cup in luteal induction but did suggest that elements of the ejaculatory reflex apart from cup formation contribute to the elicitation of this neuroendocrine response. The origin of this stimulatory effect was not directly determined, but indirect evidence suggested a role for penile spines. In Experiments 2 and 3, features of the glans penis that might help effect plug removal were investigated, and the experiments demonstrated that penile spines, perhaps in conjunction with penile cups, contribute to the extraction of plugs from the vagina. 相似文献