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1.
Mathematical theory of voting and social choice has attracted much attention. In the general setting one can view social choice as a method of aggregating individual, often conflicting preferences and making a choice that is the best compromise. How preferences are expressed and what is the “best compromise” varies and heavily depends on a particular situation. The method we propose in this paper depends on expressing individual preferences of voters and specifying properties of the resulting ranking by means of first-order formulas. Then, as a technical tool, we use methods of second-order quantifier elimination to analyze and compute results of voting. We show how to specify voting, how to compute resulting rankings and how to verify voting protocols.  相似文献   

2.
Eliminating behavior with reinforcement   总被引:3,自引:3,他引:0       下载免费PDF全文
Responding produced food according to a fixed-ratio schedule while the prevailing key-color alternated between red and blue. Stimulus durations were varied until a period was found that maintained equal rates of responding in the presence of both colors. Then, food presentation was discontinued in the presence of one stimulus and made dependent on not responding in the presence of the other. Food presentation dependent on not responding reduced the rate of responding faster than did extinction. Spontaneous recovery occurred only during the stimulus correlated with extinction.  相似文献   

3.
Six experiments investigated the memory blocking effect (MBE) in which exposure to orthographically similar words (e.g., BALLOON) impairs one's ability to complete a similar fragment (e.g., BAL_ON_, solution is BALCONY). Experiments 1 and 2 demonstrated that blocking is not observed after a 72-hour delay; however, repetition priming was observed after the same delay. Experiments 3 and 4 showed that presenting unrelated semantic information during the fragment completion test eliminates blocking. Experiment 5 demonstrated that the MBE persists despite directed-forgetting instructions, and Experiments 5 and 6 demonstrated that activating both the solutions and blocking words for a particular fragment at study eliminates blocking. Collectively, the data demonstrate that reading orthographically similar primes automatically triggers retrieval of the blocking word and an executive control process works to manage this interference. A working framework that describes how an executive control mechanism could govern memory retrieval in the memory-blocking paradigm is presented to stimulate development of more advanced theoretical models that can explain blocking.  相似文献   

4.
Six experiments investigated the memory blocking effect (MBE) in which exposure to orthographically similar words (e.g., BALLOON) impairs one's ability to complete a similar fragment (e.g., BAL_ON_, solution is BALCONY). Experiments 1 and 2 demonstrated that blocking is not observed after a 72-hour delay; however, repetition priming was observed after the same delay. Experiments 3 and 4 showed that presenting unrelated semantic information during the fragment completion test eliminates blocking. Experiment 5 demonstrated that the MBE persists despite directed-forgetting instructions, and Experiments 5 and 6 demonstrated that activating both the solutions and blocking words for a particular fragment at study eliminates blocking. Collectively, the data demonstrate that reading orthographically similar primes automatically triggers retrieval of the blocking word and an executive control process works to manage this interference. A working framework that describes how an executive control mechanism could govern memory retrieval in the memory-blocking paradigm is presented to stimulate development of more advanced theoretical models that can explain blocking.  相似文献   

5.
A sample of 6,370 students in Grades 6 to 8 completed a questionnaire on their attitudes and use of alcohol, tobacco, and other drugs. A subsample showed questionable data based on three criteria: missing responses, invalid responses, and inconsistent responses. Analysis indicated that this subsample was significantly different from the main group on demographic variables and self-reported life-time tobacco use. Results support efforts to identify and eliminate invalid data.  相似文献   

6.
Fingernail-biting is prevalent among children and adults alike. About 43% of children bite their nails during the puberty ages (Wechsler, 1931); 25% of college students are nail-biters (Coleman and McCalley, 1948), and 10% of adults bite their nails (Pennington, 1945).A variety of treatments including negative practice, operant procedures and psychotherapy have been used in treating nail-biting but no single treatment has been generally effective in eliminating nail-biting. Smith (1957) using negative practice reported that 21 of 57 (39%) of his nail-biting clients were cured. 9 improved and 27 (47%) were unimproved. Bucher (1968) reported that 13 of 20 (65%) college students stopped nail-biting by using a self-administered operant shock procedure. However, he reported many relapses after the withdrawal of shock for nail-biting. No evaluation of psychoanalytic treatment for nail-biting appears to have been made.  相似文献   

7.
I want to stop smoking, any number of procedures can be recommended as effective temporarily. However, follow-up data for these methods are often lacking or disappointing (Marston and McFall, 1971). The two purposes of this study were to (a) replicate and provide follow-up data for a promising method developed by Upper and Meredith (1970), and (b) compare the success of those who set out to “quit” versus those trying merely to “cut down”. The method used is based on the theory that if smoking can be brought under the control of a single stimulus rather than the usual, multiple elicitors, then it can be more easily modified. The stimulus used in this particular approach was the buzz of a pocket timer.  相似文献   

8.
9.
Women, the largest group of “minority” workers, are actively seeking to reduce inequities in opportunities for career development. Counselors and clinicians, who as a group have been found to hold sex-role stereotypes, probably restrict the career opportunities of women. Vocational counselors of women need to consider key questions such as the number of children women would like to have. Researchers, in studying the job performance of highly educated women, need to investigate the amount of financial, clerical, and student assistance received by men and women scholars. Such research might in part explain sex differences in research productivity.  相似文献   

10.
Eliminating the cost of task set reconfiguration   总被引:5,自引:0,他引:5  
With insufficient time to fully prepare for a switch in task, a deterioration in performance on the first trial of a new task would be expected. The interest of researchers has been captured by the residual switch costs that, surprisingly, remain despite sufficient time to prepare. We used avery simple task to investigate the costs to reaction time and accuracy associated with changing between two different instructional sets every eight trials. Subjects responded to left and right visual targets by making either spatially compatible or incompatible eye movements (Experiment 1) or buttonpress responses (Experiment 2). The subjects were cued as to whether to make the compatible or the incompatible response by the color of a border appearing on the perimeter of the display. In cases in which the subject alternated between making pro- and antisaccades, the large costs to reaction time and accuracy at the short cue-target stimulus onset asynchrony were completely eliminated when sufficient time was provided to prepare for the switch. This complete elimination of residual switch costs was not obtained when the same alternation was applied to manual responses. This pattern of results links residual costs to response selection processes and suggests that they are not a necessary component of the switch process. We propose that the elimination of "stubborn" residual switch costs is rooted in our use of a hypercompatible task (making saccades toward targets) that places minimal demands on response selection.  相似文献   

11.
12.
The dominant viewpoint regarding phonologically driven speech errors is that segments are the units responsible behind the errors. The goal of this paper is to illustrate the point that other potential candidates for explaining these speech errors, which have gone largely unnoticed, provide a better explanatory framework for speech errors than do segments. By looking at unambiguous cases and patterns of markedness, it can be shown that there exists good evidence for features and prosodic constituents in speech errors, but never any positive evidence for segments. All of these considerations taken into account together lend strong support to the argument that there is no need for a segmental level of analysis in phonology.  相似文献   

13.
14.
Three experiments investigated the relation between visual scanning demands, reaction time (RT), and psychometrically defined intelligence (IQ). Prior studies have shown reliable correlations between RT and IQ in the range of −.20 to −.80. However, these studies have confounded the number of possible stimuli (stimulus uncertainty) with the size of the area in which the stimuli may appear (visual angle). Experiment 1 replicated these studies retaining this confound. As the number of stimuli increased from one to eight, the visual angle was permitted to increase as well (from 0° to 30°). The results showed that RT varied in accord with Hick's (1952) law, and a median correlation between IQ and six RT parameters (subjects' mean RTs and standard deviations at three levels of stimulus uncertainty) of −.47 was observed. Experiment 2 removed the confound, varying only stimulus uncertainty, and the median IQ-RT correlation declined to −.02. Experiment 3 held stimulus uncertainty constant at 1 bit (two stimuli) and varied visual angle; a median correlation of −.19 was observed. It was concluded that many of the previously reported correlations may not have hinged on speed of information processing alone, but at least in part on subjects' abilities to scan the display across which the stimuli appeared.  相似文献   

15.
16.
Utilizing a particular case study of a woman attempting to come to terms with her death, this article explores the difficult metaphors of death present within the Christian tradition. Tracing a Christian understanding of death back to the work of Augustine, the case study is utilized to highlight the difficulties presented by past and present theology embracing ideas of punishment within death. Following the trajectory of the case study, alternative understandings of death present in recent Christian theology and within Native American spirituality are presented in an attempt to find room for a fuller meaning of death post-reconciliation, but premortem.  相似文献   

17.
Abstract

During public health crises including the COVID-19 pandemic, resource scarcity and contagion risks may require health systems to shift—to some degree—from a usual clinical ethic, focused on the well-being of individual patients, to a public health ethic, focused on population health. Many triage policies exist that fall under the legal protections afforded by “crisis standards of care,” but they have key differences. We critically appraise one of the most fundamental differences among policies, namely the use of criteria to categorically exclude certain patients from eligibility for otherwise standard medical services. We examine these categorical exclusion criteria from ethical, legal, disability, and implementation perspectives. Focusing our analysis on the most common type of exclusion criteria, which are disease-specific, we conclude that optimal policies for critical care resource allocation and the use of cardiopulmonary resuscitation (CPR) should not use categorical exclusions. We argue that the avoidance of categorical exclusions is often practically feasible, consistent with public health norms, and mitigates discrimination against persons with disabilities.  相似文献   

18.
Cerebral death     
Theoretical Medicine and Bioethics - The notion of cerebral death is examined in relation to those of cardiopulmonary and whole-brain death. It is argued that rather than being a new concept of...  相似文献   

19.
20.
Chemical death     
Corporate Killing: Bhopals Will Happen, by Tara Jones, London: Free Association Books, 1988, 336 pages, pb £9.95.

Bhopal: The Lessons of a Tragedy, by Sanjoy Hazarika, London: Penguin, 1987, 230 pages, pb £4.50.

Introduction to Toxicology, by J. A. Timbrell, London: Taylor and Francis, 1989, 155 pages (large format), pb £9.95.  相似文献   

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