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991.
Villarino Vivas A Reales Avilés JM Fontes de Gracia AI Fontes de Gracia S 《Psicothema》2008,20(2):331-336
Taking into account the studies about the measure of sensitivity in magnitude estimation tasks, we analyze the three most common measures used in this topic: Pearson's product-moment correlation between the logarithm of the stimulus and the logarithm of the response (R), the exponent of Stevens' power function (K), and the measure "M" proposed by Garriga-Trillo. Using a sample of participants greater than usual in psychophysical studies (180 participants), we designed an experiment with two sets of stimuli with different stimulus ranges. In each of these sets, we used two kinds of stimuli (line segments and squares). Our conclusions were: (1) we rejected the use of K as a sensitivity measure because the results provided by this index were the opposite of those expected when we compared the two stimulus ranges. (2) We also rejected the use of M because this measure is a linear transformation of Kendall's coefficient of concordance. (3) Lastly, we suggest the mathematical transformation proposed by Fisher to achieve a normal distribution, and recommend this transformation as the best sensitivity measure. 相似文献
992.
Galán Rodríguez A Pérez San Gregorio AM Martín Rodríguez A Borda Más M 《Psicothema》2008,20(2):266-272
Transplantation may imply severe biopsychosocial impairments. In order to know the quality of life of patients one year after transplantation, 58 subjects were compared to three different groups of patients (stabilized and acute COPD patients, and lung cancer patients in a surgery unit). Patients filled in two questionnaires: EORTC QLQ-C30 (quality of life) and HAD (anxiety and depression). The quality of life dimensions with inter-group differences were physical, role, emotional and cognitive functioning, global health status, and a number of symptoms (fatigue, dyspnea, insomnia and appetite loss). There were differences in depression, and but not in anxiety. Transplant and surgical patients showed better quality of life and affective status than chronic pulmonary patients. Discriminant analysis showed that the transplant group was the best described group. We conclude that patients, one year after transplantation, show similar quality of life as asymptomatic hospitalised patients, somewhat better than chronic patients in a stabilized stage of the disease, and much better than severe chronic patients. 相似文献
993.
Jarno Jansen Carolina de Weerth J. Marianne Riksen-Walraven 《Developmental Review》2008,28(4):503-521
A positive effect of breastfeeding on the mother–infant relationship is often assumed in the scientific literature, but this has not been systematically reviewed. This review aims to clarify the role of breastfeeding in the mother–infant relationship, which is conceptualized as the maternal bond toward the infant and infant attachment toward the mother. Our findings indicate that theoretical mechanisms through which breastfeeding may enhance the maternal bond or infant attachment (i.e., endocrine and sensory factors involved in breastfeeding) can be found in both humans and animal models. However, the few empirical studies investigating this association have not found convincing support for a relation between breastfeeding and the quality of the mother–infant relationship. We therefore conclude that assumptions on a positive role of breastfeeding on the mother–infant relationship are not supported by empirical evidence, and recommendation of breastfeeding should solely be based on its well-documented positive effects on infant and maternal health. 相似文献
994.
Facial expression and direction of gaze are two important sources of social information, and what message each conveys may ultimately depend on how the respective information interacts in the eye of the perceiver. Direct gaze signals an interaction with the observer but averted gaze amounts to "pointing with the eyes", and in combination with a fearful facial expression may signal the presence of environmental danger. We used fMRI to examine how gaze direction influences brain processing of facial expression of fear. The combination of fearful faces and averted gazes activated areas related to gaze shifting (STS, IPS) and fear-processing (amygdala, hypothalamus, pallidum). Additional modulation of activation was observed in motion detection areas, in premotor areas and in the somatosensory cortex, bilaterally. Our results indicate that the direction of gaze prompts a process whereby the brain combines the meaning of the facial expression with the information provided by gaze direction, and in the process computes the behavioral implications for the observer. 相似文献
995.
We investigated the role of transparency, perceptual grouping, and presentation time on perceived lightness. Both transparency and perceptual grouping have been found to result in assimilation effects, but only for ambiguous stimulus displays and with specific attentional instructions. By varying the presentation times of displays with two partly overlapping transparent E-shaped objects, we measured assimilation in unambiguous stimulus displays and without specific attentional instructions. The task was to judge which of two simultaneously presented E-shaped objects was darker. With unrestrained presentation times, if a transparency interpretation was possible, assimilation was not found. Inhibiting a transparency interpretation by occluding the local junctions between the two E-shaped objects, did lead to assimilation. With short presentation times, if a transparency interpretation was possible, assimilation was now also found. Thus, we conclude that, although transparency appears to enhance assimilation, with unambiguous stimulus displays and without specific attentional instructions, perceptual grouping is more important for assimilation to occur. 相似文献
996.
Helga A. G. de Valk 《Sex roles》2008,59(9-10):738-751
This paper examined the work and family plans of adolescents from five different ethnic origins. The way in which parents influence these plans was studied by using a representative sample of secondary school pupils (N?=?52,000) in The Netherlands. Results showed that substantial proportions of adolescents had traditional work and family plans. The study showed that work and family plans of adolescents of non-Dutch origin overall were at least as egalitarian as those of Dutch origin. Girls of all ethnic origins held more egalitarian plans than boys. Logistic regression analyses revealed that adolescents’ plans were associated with parents’ socio-demographic characteristics and role-modeling. The processes of intergenerational transmission were found to be highly similar for girls and boys in all ethnic groups. 相似文献
997.
Epistemic naturalism holds that the results or methodologies from the cognitive sciences are relevant to epistemology, and
some have maintained that scientific methods are more compatible with externalist theories of justification than with internalist
theories. But practically all discussions about naturalized epistemology are framed exclusively in terms of cognitive psychology,
which is only one of the cognitive sciences. The question addressed in this essay is whether a commitment to naturalism really
does favor externalism over internalism, and we offer reasons for thinking that naturalism in epistemology is compatible with
both internalist and externalist conceptions of justification. We also argue that there are some distinctively internalist
aims that are currently being studied scientifically and these notions, and others, should be studied by scientific methods.
This essay is dedicated to Deborah Mayo, who has long advocated using error statistical techniques to analyze and resolve
epistemological puzzles in the philosophy of science. This essay follows the same spirit by advocating that computational
concepts and techniques be applied within the heart of traditional, analytic epistemology. 相似文献
998.
Dan López de Sa 《Synthese》2008,163(2):263-272
According to the simple proposal, a predicate is rigid iff it signifies the same property across the different possible worlds. The simple proposal has been
claimed to suffer from an over-generalization problem. Assume that one can make sense of predicates signifying properties, and assume that trivialization concerns, to the effect
that the notion would cover any predicate whatsoever, can be overcome. Still, the proposal would over-generalize, the worry
has it, by covering predicates for artifactual, social, or evaluative properties, such as ‘is a knife,’ ‘is a bachelor,’ or
‘is funny.’ In defense, it is argued that rigidity for predicates as characterized plays the appropriate theoretical role,
and that the contention that “unnatural” properties are not to be rigidly signified is ungrounded. 相似文献
999.
1000.
Flvio L.C. de Moura Mauricio Ayala-Rincn Fairouz Kamareddine 《Journal of Applied Logic》2008,6(1):72-108
We compare two different styles of Higher-Order Unification (HOU): the classical HOU algorithm of Huet for the simply typed λ-calculus and HOU based on the λσ-calculus of explicit substitutions. For doing so, first, the original Huet algorithm for the simply typed λ-calculus with names is adapted to the language of the λ-calculus in de Bruijn's notation, since this is the notation used by the λσ-calculus. Afterwards, we introduce a new structural notation called unification tree, which eases the presentation of the subgoals generated by Huet's algorithm and its behaviour. The unification tree notation will be important for the comparison between Huet's algorithm and unification in the λσ-calculus whose derivations are presented into a structure called derivation tree. We prove that there exists an important structural correspondence between Huet's HOU and the λσ-HOU method: for each (sub-)problem in the unification tree there exists a counterpart in the derivation tree. This allows us to conclude that the λσ-HOU is a generalization of Huet's algorithm and that solutions computed by the latter are always computed by the former method. 相似文献