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851.
    
This paper introduces a method for finding the non‐dominated set in criterion space of an MOLP problem based on Fourier–Motzkin Elimination. The method incorporates a procedure that eliminates decision variables from constraints and transforms a feasible region from decision space to criterion space. While avoiding characterization of the efficient set in decision space, it finds the non‐dominated set in criterion space. After the decision maker's most preferred criterion vector has been identified, the corresponding efficient solutions can be found by backward substitution. The method was implemented in MATLAB using a tabular form and computational experiments were conducted. The results indicate that although the method performs well for relatively small problems, it can be computationally intensive for larger problems. Nonetheless, the method is intuitively appealing and it provides useful insights into the geometry and theory of MOLP. As such it makes it a valuable educational tool for students of multi‐criteria decision analysis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
852.
    
An intermediate step is introduced to the dialogue decision process for decision analysis. Alternatives are refined after they have been generated within a strategy table but before they are subject to more detailed evaluation. Two or more judges create a subjective mapping from alternatives to attributes that will later be mapped to criteria. In strategy tables, each of the alternative strategies consists of a coherent set of choices made across several decisions that are to be coordinated. These strategic alternatives are modified so as to increase their differentiation in the attribute space, rather than in the decision space alone. When criteria weights are unknown, the best alternative from the modified set may be superior to the best alternative from the original set. Furthermore, analysis of the resulting alternatives may yield a better mapping of the value response surface for the action space, in the sense that this mapping leads to eventual construction of a higher value alternative. Results are reported for a consulting engagement incorporating the proposed step. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
853.
    
What are the prospects for consumerism? Often despised as self‐indulgent, consumers are frequently motivated by altruism and their needs to express their identity, to build relationships, to obtain fulfilment and even to find a substitute for religion. Mass‐customisation is producing fundamental change, revolutionising attitudes to choice, with a key role for agents (human and online) in helping people choose. Consumer power will grow and brands will be under pressure from rising consumer expectations. While retailers fight back with targeted marketing and special offers, brands will need to serve consumer needs as much as suppliers. Online shopping could transform consumer behaviour, driven by cost saving and convenience and spurred on by competition. Will retailers protect their traditional channels or go online because they are afraid not to? ‘Etailing’ will need to create consumer trust, so regulation will be critical, possibly leading to legal responsibilities for quality on Internet service providers (ISPs) and portals and with systems to help new entrants build a track record of reliability, thereby increasing competition, choice and consumer power. Copyright © 2002 Henry Stewart Publications.  相似文献   
854.
    
This study focuses on the effect of restrictive information display on decision performance. Specifically the study examines whether two‐channeled and one non‐channeled computerized information display systems result in significant differences in decision accuracy. The two‐channeled information display systems are designed to encourage two general information processing patterns commonly observed in the experimental literature examining multi‐alternative, multi‐attribute choice decisions: information processing by alternative and information processing by attribute. An information display program was developed which used restrictive information display to operationalize the channeled versus non‐channeled manipulation. Channeling was implemented either by displaying information only by alternative or by displaying information only by attribute. The task was an operations scheduling problem that subjects completed under three levels of time pressure. The results indicate statistically significant effects on decision accuracy for both the type of information display and time pressure manipulations. The highest decision accuracy was observed when information was displayed by alternative and when subjects were under highest levels of time pressure. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
855.
    
The aim of this study was to explore, in depth, the perceptions and experiences of Further Education (FE) amongst the young long‐term unemployed. Semi‐structured interviews were conducted with 16 long‐term unemployed youths of 18–25 years of age divided into three groups: those with no experience of FE; those having recently dropped out of FE; and those currently studying in FE. Grounded theoretical analysis highlighted the importance of both responses to and institutional aspects of unemployment. The impact of unemployment, poor previous educational experience and perceived irrelevance of FE are key barriers to learning. Those that enter FE may drop out as a result of both material and psychosocial factors. Those that stay on commonly emphasize both social support and personal agency in decision‐making alongside positive evaluations of FE. In conclusion, limitations of the findings, policy and practical recommendations for successful widening of participation in FE amongst this group are considered. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
856.
    
Recent research suggests that children's understanding of self‐presentational behaviour—behaviour designed to shape social evaluation—is a function of both cognitive and motivational variables. Furthermore, the motivational factors involved are likely to reflect individual differences in the salience of concerns about social evaluation. The present research represents a first effort to determine whether measures of such differences are indeed associated with the understanding of self‐presentational behaviour. In a first experiment, a teacher rating measure of self‐monitoring was found to be positively associated with the understanding of self‐presentational motives. In a second experiment, a more narrowly specified self‐report measure of public self‐consciousness was found to have a similar association with the understanding of self‐presentation, with no such association found for private self‐consciousness. These preliminary results make it clear that our formulations of development in social cognition must indeed include a consideration of individual differences in motivational orientations. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
857.
    
We investigated the sibling relationship as a context for cognitive development. Forty preschoolers (ages 5–6) and their younger siblings (ages 2–3) were visited at home. Four games were presented to the older siblings and they were asked (a) to estimate how well their younger sibling will perform on each game and (b) to teach the younger sibling how to use the games. The older siblings' mediating behaviours during the teaching session and the younger siblings' performance on the four tasks were coded. The frequency of mediating behaviours—including attention focusing, amplifying affect and providing meaning, fostering a sense of competence, regulating of the learning process, de‐contextualization, and negative feedback in the form of mocking and laughing at errors, predicted the younger siblings' task performance. The older sibling's accurate perception of the younger child's competence was uniquely predictive of task performance. The highest amount of mediation was observed in older‐brother–younger‐brother pairs, in particular the behaviours of negative feedback and amplifying affect. Results contribute to the discussion on the role of siblings as moderators of cognitive development and are discussed in terms of Vygotsky's cultural–historical perspective on apprenticeship. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
858.
    
This paper considers the question whether a psychological approach to personal identity can be formulated within an endurantist, as opposed to four‐dimensionalist, framework. Trenton Merricks has argued that this cannot be done. I argue to the contrary: a perfectly coherent endurantist version of the psychological approach can indeed be formulated.  相似文献   
859.
    
Food‐deprived rats in Experiment 1 responded to one of two tandem schedules that were, with equal probability, associated with a sample lever. The tandem schedules' initial links were different random‐interval schedules. Their values were adjusted to approximate equality in time to completing each tandem schedule's response requirements. The tandem schedules differed in their terminal links: One reinforced short interresponse times; the other reinforced long ones. Tandem‐schedule completion presented two comparison levers, one of which was associated with each tandem schedule. Pressing the lever associated with the sample‐lever tandem schedule produced a food pellet. Pressing the other produced a blackout. The difference between terminal‐link reinforced interresponse times varied across 10‐trial blocks within a session. Conditional‐discrimination accuracy increased with the size of the temporal difference between terminal‐link reinforced interresponse times. In Experiment 2, one tandem schedule was replaced by a random ratio, while the comparison schedule was either a tandem schedule that only reinforced long interresponse times or a random‐interval schedule. Again, conditional‐discrimination accuracy increased with the temporal difference between the two schedules' reinforced interresponse times. Most rats mastered the discrimination between random ratio and random interval, showing that the interresponse times reinforced by these schedules can serve to discriminate between these schedules.  相似文献   
860.
    
There is evidence suggesting aggression may be a positive reinforcer in many species. However, only a few studies have examined the characteristics of aggression as a positive reinforcer in mice. Four types of reinforcement schedules were examined in the current experiment using male Swiss CFW albino mice in a resident—intruder model of aggression as a positive reinforcer. A nose poke response on an operant conditioning panel was reinforced under fixed‐ratio (FR 8), fixed‐interval (FI 5‐min), progressive ratio (PR 2), or differential reinforcement of low rate behavior reinforcement schedules (DRL 40‐s and DRL 80‐s). In the FR conditions, nose pokes were maintained by aggression and extinguished when the aggression contingency was removed. There were long postreinforcement pauses followed by bursts of responses with short interresponse times (IRTs). In the FI conditions, nose pokes were maintained by aggression, occurred more frequently as the interval elapsed, and extinguished when the contingency was removed. In the PR conditions, nose pokes were maintained by aggression, postreinforcement pauses increased as the ratio requirement increased, and responding was extinguished when the aggression contingency was removed. In the DRL conditions, the nose poke rate decreased, while the proportional distributions of IRTs and postreinforcement pauses shifted toward longer durations as the DRL interval increased. However, most responses occurred before the minimum IRT interval elapsed, suggesting weak temporal control of behavior. Overall, the findings suggest aggression can be a positive reinforcer for nose poke responses in mice on ratio‐ and time‐based reinforcement schedules.  相似文献   
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