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981.
982.
Attitudinal ambivalence is generally construed as existing when the same attitude object is evaluated simultaneously as both positive and negative. The present research examined the moderating role of attitudinal ambivalence (as assessed by split‐semantic differential measure) on the relationship between bipolar semantic differential measures of attitude and subsequent behaviour using moderated regression analysis. In Study 1, higher levels of attitudinal ambivalence were shown to result in weaker attitude–behaviour relationships for eating a low‐fat diet (N = 140) and eating 5 portions of fruit and vegetables per day (N = 142). Study 2 (N = 361) replicated this effect when also including a measure of past behaviour for eating a low‐fat diet. Implications for understanding the relationship between attitudes and behaviour are discussed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
983.
984.
To dispel apparent confusion, White racial identity and White racial consciousness are described and contrasted in terms of theoretical conceptualization and measures used. It is recommended that priority be given to the validation of existing or new measurement instruments to provide a sound basis for future findings. Para disipar la confusión aparente, la identidad racial Bianca, y el conocimiento racial Blanco, se describen y son contrastados en términos de sus conceptos teóricos y las medidas empleadas. Se recomienda dar prioridad a la validación de instrumentos existentes o nuevos para proporcionar una base sólida para los deseubrimientos futuros.  相似文献   
985.
986.
The learning of an association between a CS and a US can be retarded by unreinforced presentations of the CS alone (termed latent inhibition or LI) or by un-correlated presentations of the CS and US (termed learned irrelevance or LIRR). In rabbit eyeblink conditioning, there have been some recent failures to replicate LI. LIRR has been hypothesized as producing a stronger retardation effect than LI based on both empirical studies and computational models. In the work presented here, we examined the relative strength of LI and LIRR in eyeblink conditioning in rabbits and humans. In both species, a number of preexposure trials sufficient to produce LIRR failed to produce LI (Experiments 1 & 3). Doubling the number of CS pre-exposures did produce LI in rabbits (Experiment 2), but not in humans (Experiment 4). LI was demonstrated in humans only after manipulations including an increased inter-trial interval or ITI (Experiment 5). Overall, it appears that LIRR is a more easily producible pre-exposure retardation effect than LI for eyeblink conditioning in both rabbits and humans. Several theoretical mechanisms for LI including the conditioned attention theory, stimulus compression, novelty, and the switching theory are discussed as possible explanations for the differences between LIRR and LI. Overall, future work involving testing the neural substrates of pre-exposure effects may benefit from the use of LIRR rather than LI.  相似文献   
987.
Clinical experience with older adults shows that many will experience PTSD symptoms in older adulthood because of trauma exposure early in life. Some of these patients struggled with PTSD in the distant past and remained symptomfree for decades only to have a recurrence of PTSD in late life. This paper outlines a cognitive aging explanation for the recurrence of PTSD. It is proposed that the age-related decreases in attention make the intrusion of trauma-related memories more likely. The increase in intrusive memories, combined with age-related decreases in working memory, explicit memory, and prospective memory, increases the subjective distress associated with the memories and results in a recurrence of PTSD.  相似文献   
988.
Advocates of an environmental ethic frequently claim that what makes an ethical theory truly and uniquely environmental is its commitment to the principle that environmental wholes such as species, ecosystems, and biotic communities are morally considerable. The prevailing view is that our primary duty towards these wholes is to respect their integrity, stability, and beauty, and that the best way to do this is to leave them alone, not interfere with them, and let nature follow its own course. But is that correct? Why should be refrain from interfering with nature? There are two ways an environmentalist might try to justify an exceptionaless, prima facie principle of noninterference. First, she might claim that there is a contingent but universal connection between human interference and ecosystemic harm. There is also an epistemic variant of this view. When faced with a decision concerning whether to interfere with an ecosystem, there will always be overwhelming reasons for thinking that interference will be harmful, regardless of the specific circumstances. Send, there might be some conceptual connection between interference and harm to ecosystems. For example, if the well-being of an ecosystem is identified with its wildness, and wildness is understood as the absence of human intervention or manipulation, then any human interference necessarily detracts from an ecosystem's wildness and thereby has a detrimental effect on its well-being. In this paper I examine these justifications in detail and argue that none can support an exceptionaless principle of noninterference.  相似文献   
989.
This paper explores the relationship between expectations and product satisfaction evaluations in a high‐involvement product category. While doing so, the paper attempts to develop a regression model to predict the overall level of consumer satisfaction derived from CD players, using a number of explanatory variables within an ordinary least squares framework. This regression model links overall satisfaction to confidence in other people's opinions, expectations of product quality, experience with product quality, replacement rate and the importance of price. The model predicts fairly well for cross‐sectional data, with an adjusted R2 of 57 per cent, and appears to be robust. Finally, the implications of these results for marketers are discussed. Copyright © 2002 Henry Stewart Publications.  相似文献   
990.
A novel three-dimensional eye tracker is described and its performance evaluated. In contrast to previous devices based on conventional video standards, the present eye tracker is based on programmable CMOS image sensors, interfaced directly to digital processing circuitry to permit real-time image acquisition and processing. This architecture provides a number of important advantages, including image sampling rates of up to 400/sec measurement, direct pixel addressing for preprocessing and acquisition, and hard-disk storage of relevant image data. The reconfigurable digital processing circuitry also facilitatesin-line optimization of the front-end, time-critical processes. The primary acquisition algorithm for tracking the pupil and other eye features is designed around the generalized Hough transform. The tracker permits comprehensive measurement of eye movement (three degrees of freedom) and head movement (six degrees of freedom), and thus provides the basis for many types of vestibulo-oculomotor and visual research. The device has been qualified by the German Space Agency (DLR) and NASA for deployment on the International Space Station. It is foreseen that the device will be used together with appropriate stimulus generators as a general purpose facility for visual and vestibular experiments. Initial verification studies with an artificial eye demonstrate a measurement resolution of better than 0.1° in all three components (i.e., system noise for each of the components measured as 0.006° H, 0.005° V, and 0.016° T. Over a range of ±20° eye rotation, linearity was found to be <0.5% (H), <0.5% (V), and <2.0% (T). A comparison with the scierai search coil technique yieldednear equivalent values for the systemnoise and the thickness of Listing’s plane.  相似文献   
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