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861.
Order structures such as linear orders, weak orders, semiorders and interval orders are often considered as models of a decision maker's preferences. In this paper we introduce and study new order structures characterized by their symmetric part belonging to certain classes of co-comparability graphs. We outline possible interpretations and suggest special representations of these structures and we point out their potential use for approximating relations obtained through a multicriteria aggregation procedure. We provide various characterizations of the new structures (as well as of older ones) in terms of minimal forbidden configurations and by algebraic conditions.  相似文献   
862.
This article presents the major stages of the approaches to the ethics of communication and the respective ethical principle of each one. The first stage, centred on the principle of truthfulness, was born at the beginning of the 20th century, at the same time as the first great development of the press and journalism. The second stage, which began at the end of the 20th century, centred on the principle of beneficence and developed from the growing influence of the mass media on all fields and aspects of social life. There is also the need for a further principle for communication ethics: the principle of vulnerability: to give voice to those affected by a situation, especially to those in a situation of vulnerability. The article then considers whether the huge impact of the Internet and social media at the beginning of the 21st century implies a new stage in the ethics of communication or rather the need to extend the scope and effectiveness of existing ethical principles and norms. The article tends toward the second option, insisting on the role of self-regulation and media literacy in tackling the current challenges in media and social media communications.  相似文献   
863.
Compared with object word learning, young children typically find learning color terms to be a difficult linguistic task. In this reflections article, I consider two questions that are fundamental to investigations into the developmental acquisition of color terms. First, I consider what constrains color term acquisition and how stable these constraints are over culture and age. I review recent studies that have identified conceptual, attentional, and linguistic constraints that seemingly operate on the acquisition of color terms compared with object words and the differential acquisition of color terms within a given language. Second, I consider whether these constraints are specific to the acquisition of color terms or whether they reflect more general constraints that operate on other classes of lexical terms such as different abstract property terms.  相似文献   
864.
This paper describes the use of a theory of change approach to community-based cross-agency service planning for children with serious emotional disturbance and their families. Public agency planners in Contra Costa County, California used the theory of change approach to organize service planning for a population of youth who had been arrested and involved with juvenile probation. The theory of change process described in this paper links community outcomes with planned activities with the assumptions or principles that underlie the community planning efforts. When complete, a theory of change logic model can serve as a guide for implementation, ensuring that community plans for service delivery remain true to their intent. The theory of change development process includes twelve stages and is based on a step-by-step approach. Theory of change logic models establish a context for articulating a community's shared beliefs and prompt local stakeholders to establish logical connections between the population to be served, expected results, and strategies intended to achieve those results.  相似文献   
865.
We present an analytic solution for a race model of n stochastic accumulators for multiple choice reaction time. We show that to maintain a constant level of accuracy, the response criterion needs to be increased approximately logarithmically with n, to compensate for the increase with n in the likelihood that an incorrect alternative will be most active after any fixed amount of time accumulating information. Assuming that participants monitor and maintain a constant level of performance can then explain the logarithmic dependency of the response latency on n as specified by Hick's law. Moreover, we show that for short time intervals, the Shannon information that observers extract from a stimulus, is predicted to increase linearly with processing time.  相似文献   
866.
Female zebra finches show a preference for male zebra finches over heterospecific males based solely on the auditory cues of males, such as songs. The present study was designed to investigate whether females show a similar preference for male zebra finches based solely on visual cues. Using a Y-maze apparatus, social preference of female zebra finches was studied between male zebra finches and male Bengalese finches in three experiments. In experiment 1, where female zebra finches could see and hear live male zebra finches and male Bengalese finches, the females preferred to associate with the male zebra finches. In experiment 2, using a sound-attenuated experimental apparatus, subjects could see, but not hear, male zebra finches and male Bengalese finches. The subjects did not show a significant preference for associating with zebra finches. In experiment 3, as in experiment 2, females could see live male zebra finches and male Bengalese finches in the sound-attenuated chambers. However, in experiment 3, the subjects also heard prerecorded auditory cues (i.e., songs and calls) of male zebra finches, which were presented simultaneously in both arms of the maze. Although the females could not use the auditory cues to identify the location of the male zebra finches, they preferred to associate with the male zebra finches rather than the male Bengalese finches. These results suggest that visual cues alone were effective in initiating choice behaviors by females and that auditory cues facilitate such visually based choice behaviors. Electronic Publication  相似文献   
867.
We compared results from two preference assessments with data on extended performance of vocational tasks by 4 participants with developmental disabilities. All participants engaged in one task exclusively when seven tasks were available concurrently during a 5-min multiple-stimulus assessment. By contrast, all participants exhibited high levels of engagement in most tasks when the tasks were presented singly for 5 min, and these data showed a high degree of correspondence with those obtained during extended (60-min) vocational assessments.  相似文献   
868.
The hypotheses of this investigation were derived by conceiving of automatic mimicking as a component of emotional empathy. Differences between subjects high and low in emotional empathy were investigated. The parameters compared were facial mimicry reactions, as represented by electromyographic (EMG) activity when subjects were exposed to pictures of angry or happy faces, and the degree of correspondence between subjects' facial EMG reactions and their self-reported feelings. The comparisons were made at different stimulus exposure times in order to elicit reactions at different levels of information processing. The high-empathy subjects were found to have a higher degree of mimicking behavior than the low-empathy subjects, a difference that emerged at short exposure times (17-40 ms) that represented automatic reactions. The low-empathy subjects tended already at short exposure times (17-40 ms) to show inverse zygomaticus muscle reactions, namely "smiling" when exposed to an angry face. The high-empathy group was characterized by a significantly higher correspondence between facial expressions and self-reported feelings. No differences were found between the high- and low-empathy subjects in their verbally reported feelings when presented a happy or an angry face. Thus, the differences between the groups in emotional empathy appeared to be related to differences in automatic somatic reactions to facial stimuli rather than to differences in their conscious interpretation of the emotional situation.  相似文献   
869.
Around 1 year of age, infants develop the ability to individuate objects in the absence of spatiotemporal information. Some have proposed that this capacity relies on the emergence of language and, in particular, that comprehending an object's label is required to individuate it as a particular kind. One approach to testing this hypothesis is to conduct experiments on pre-linguistic human infants. A second is to test non-linguistic animals. We followed the second approach, exploring whether semi-free-ranging rhesus macaques can individuate objects using property/kind information. To make the results most directly comparable, we adapted a reaching paradigm used to examine property/kind individuation in infants. Results from three experiments demonstrate that, like 12-month-old infants, adult rhesus macaques can use both spatiotemporal and property/kind information to individuate food objects. In a fourth experiment designed to examine which properties are used to individuate food objects, results revealed that rhesus use color, but not shape. These results, together with experiments involving different procedures, provide support for the conclusion that in the absence of linguistic abilities, some non-human primates spontaneously use property/kind information to individuate objects.  相似文献   
870.
Two experiments asked whether resistance to change depended on variable-ratio as opposed to variable-interval contingencies of reinforcement and the different response rates they establish. In Experiment 1, pigeons were trained on multiple random-ratio random-interval schedules with equated reinforcer rates. Baseline response rates were disrupted by intercomponent food, extinction, and prefeeding. Resistance to change relative to baseline was greater in the interval component, and the difference was correlated with the extent to which baseline response rates were higher in the ratio component. In Experiment 2, pigeons were trained on multiple variable-ratio variable-interval schedules in one half of each session and on concurrent chains in the other half in which the terminal links corresponded to the multiple-schedule components. The schedules were varied over six conditions, including two with equated reinforcer rates. In concurrent chains, preference strongly overmatched the ratio of obtained reinforcer rates. In multiple schedules, relative resistance to response-independent food during intercomponent intervals, extinction, and intercomponent food plus extinction depended on the ratio of obtained reinforcer rates but was less sensitive than was preference. When reinforcer rates were similar, both preference and relative resistance were greater for the variable-interval schedule, and the differences were correlated with the extent to which baseline response rates were higher on the variable-ratio schedule, confirming the results of Experiment 1. These results demonstrate that resistance to change and preference depend in part on response rate as well as obtained reinforcer rate, and challenge the independence of resistance to change and preference with respect to response rate proposed by behavioral momentum theory.  相似文献   
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