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41.
W. M. de Muynck 《Synthese》1995,102(2):293-318
The axiomatic approaches of quantum mechanics and relativity theory are compared with approaches in which the theories are thought to describe readings of certain measurement operations. The usual axioms are shown to correspond with classes of ideal measurements. The necessity is discussed of generalizing the formalisms of both quantum mechanics and relativity theory so as to encompass more realistic nonideal measurements. It is argued that this generalization favours an empiricist interpretation of the mathematical formalisms over a realist one.  相似文献   
42.
The purpose of the present study was to compare the oculomotor behavior of readers scanning meaningful and meaningless materials. Four conditions were used—a normal-text-reading control condition, and three experimental conditions in which the amount of linguistic processing was reduced, either by presenting the subjects with repeated letter strings or by asking the subjects to search for a target letter in texts or letter strings. The results show that global eye-movement characteristics (such as saccade size and fixation duration), as well as local characteristics (such as word-skipping rate, landing site, refixation probability, and refixation position), are very similar in the four conditions. The finding that the eyes are capable of generating an autonomous oculomotor scanning strategy in the absence of any linguistic information to process argues in favor of the idea that such predetermined oculomotor strategies might be an important determinant of eye movements in reading.  相似文献   
43.
A seminal attentional model of time estimation predicts that subjective duration will be positively correlated to the amount of attention given to temporal processing. This prediction holds under prospective conditions, in which one is forewarned that judgments of time will be asked, in contrast to retrospective conditions, in which such judgments are required after the relevant period without any prior warning. In three experiments, an attention-sharing method was used. Subjects were asked to control the amount of attention that they devoted to one or the other component of a dual-task paradigm. The first experiment involved word categorization and reproduction of duration. The following experiments, based on signal detection theory, required discrimination of both the duration and the intensity of a single stimulus, in the visual (Experiment 2) or the auditory (Experiment 3) modality. The results indicate that when the attention is directly controlled by the subject, the subjective duration shortens as the amount of attention devoted to the temporal task diminishes. The implications of these results for the possible existence of an internal timer are considered.  相似文献   
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Although there are measurable differences in integrative complexity among solutions that individuals generate in dealing with problems, it is uncertain to what extent people comprehend, recognize, and have preferences among different levels of complexity. Integrative complexity is a function of differentiation (the perception of several attributes within, or perspectives about, a topic) and integration (combining the differentiated characteristics in an interactive or synthesizing solution). The current paper reports two experiments dealing with how university students perceive, interpret, and choose among solutions differing in complexity. Experiment 1 showed that subjects accurately rated the complexity of described solutions differing along the continuum, but that their assessment of their own responses differed from the results of expert scoring. Their self-estimated complexity was highly correlated with their preferences, and preferred complexity was reliably higher than either expert- or self-assessed complexity of subject-generated solutions. Subjects were able to hypothesize quite accurately about environmental and endogenous factors likely to affect complexity. Experiment 2 found that in response to problem scenarios, solutions selected as being potentially most effective were consistently more complex than solutions that participants considered themselves most likely to use. The idea of complexity seems to be intuitively recognizable and understandable by untrained subjects: They can and do distinguish among problem solutions (self-generated or presented) that vary on that dimension, and are able to assess accurately the effects of relevant variables. Such subjects also share the bias shown by experts in favour of the superiority of more complex approaches.  相似文献   
47.
This study was designed to examine the relationship between gender role orientation and psychological adjustment during pregnancy and the postpartum period in a large sample of French-speaking Caucasian mothers. Gender role was assessed with the Bem Sex Role Inventory, which classifies subjects into four categories: androgynous, masculine, feminine, and undifferentiated. A discriminant analysis showed a relationship between androgyny and the following measures of psychological adaptation: self-esteem, satisfaction with social support, and level of apprehension toward perinatal stressors. The masculine gender role was linked with self-esteem, work involvement, age, and severity of perinatal stress. No relationship was found between gender role and the level of antenatal or postnatal depressive symptomatology. Stress, marital support, and social support were among the predictors of postpartum depression, which underlined the importance of taking these variables into account when studying the well-being of mothers during the postnatal period. Results are discussed in light of previous literature on the association between gender role and motherhood. The limitations of Bem's model and inventory are also considered.  相似文献   
48.
In studies related to human movement, linked segment models (LSM's) are often used to quantify forces and torques, generated in body joints. Some LSM's represent only a few body segments. Others, for instance used in studies on the control of whole body movements, include all body segments. As a consequence of the complexity of 3-dimensional (3-D) analyses, most LSM's are restricted to one plane of motion. However, in asymmetric movements this may result in a loss of relevant information. The aim of the current study was to develop and validate a 3-D LSM including all body segments. Braces with markers, attached to all body segments, were used to record the body movements. The validation of the model was accomplished by comparing the measured with the estimated ground reaction force and by comparing the torques at the lumbo-sacral joint that resulted from a bottom-up and a top-down mechanical analysis. For both comparisons, reasonable to good agreement was found. Sources of error that could not be analysed this way, were subjected to an additional sensitivity analysis. It was concluded that the internal validity of the current model is quite satisfactory.  相似文献   
49.
Two experiments were carried out in order to try to resolve the controversy about whether the semantic processing of a word necessarily involves all the elements of its meaning. In the first experiment, subjects categorized a list of auditorially presented words according to whether or not they were natural consumable solids (e.g., “apple“). They were then given an unexpected test of their ability to recall the whole list, which contained equal numbers of words with none, one, two, or all three of the target components. The results confirmed the prediction that the greater the number of components a word has in common with a target category, the better it will be recalled. The second experiment used a visual presentation of a list of words, which subjects scanned for members of a particular target category. There were four different target categories assigned to independent groups of subjects. The results again confirmed the prediction. On the assumption that memorability in such tasks is determined by amount of processing, we conclude that some elements of the meaning of a word can be processed without having to process all of them.  相似文献   
50.
A new computational method to fit the weighted euclidean distance model   总被引:1,自引:0,他引:1  
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper.  相似文献   
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