基于文档重排列的中文信息检索系统(英文)

对于文本信息检索,用户都希望从被检索出来的前N篇文章中得到更多的相关信息。本文介绍一个基于文档重排列的中文信息检索系统。为了通过重排列初检索文本来提高检索结果的精确率,该系统按照初检索结果中前100个排列文档中的关键词的分布对结果中的所有1000个文档进行重排列。实验中使用NTCIR-3正式的中文测试数据作为测试集,结果表明,该系统对中文文本检索精确率的提高取得一定的效果。     

Emotions as strategic information: Effects of other’s emotional expressions on fixed-pie perception, demands, and integrative behavior in negotiation

Negotiators often fail to reach integrative (”win-win”) agreements because they think that their own and other’s preferences are diametrically opposed—the so-called fixed-pie perception. We examined how verbal (Experiment 1) and nonverbal (Experiment 2) emotional expressions may reduce fixed-pie perception and promote integrative behavior. In a two-issue computer-simulated negotiation, participants negotiated with a counterpart emitting one of the following emotional response patterns: (1) anger on both issues, (2) anger on participant’s high priority issue and happiness on participant’s low-priority issue, (3) happiness on high priority issue and anger on low-priority issue, or (4) happiness on both issues. In both studies, the third pattern reduced fixed-pie perception and increased integrative behavior, whereas the second pattern amplified bias and reduced integrative behavior. Implications for how emotions shape social exchange are discussed.     

In the mood to face the facts: When a positive mood promotes systematic processing of self-threatening information

Two experiments tested the hypothesis that a positive mood can increase attendance to, and systematic processing of, threatening health information, particularly when the information is self-relevant. In Study 1, a positive mood increased differentiation between strong and weak arguments in a threatening health message about RSI only for participants who had received false feedback regarding their high vulnerability to RSI. Mood had no effects under conditions of low vulnerability. In Study 2, a positive mood speeded up responses to self-threatening words—compared with neutral words—for smokers who had just read a threatening health message about smoking. The authors conclude that fostering a positive mood may promote attendance to and systematic processing of information that threatens the self, and hence contribute to the success of health campaigns targeted at individuals who are vulnerable to specific health risks.

In the absence of rose-colored glasses: Ratings of self-attributes and their differential certainty and importance across multiple dimensions in social phobia

Sixty-seven individuals with social phobia (social anxiety disorder) and 60 healthy controls rated their perceived standing relative to others on 13 self-attribute dimensions, their level of certainty concerning those standings, and the importance of each dimension. As expected, individuals with social phobia provided self-ratings that were significantly more negative than controls across all dimensions. In addition, positive self-views were equated with higher levels of certainty and importance for controls, but not for individuals with social phobia. Thus, whereas reports of control participants reflected a healthy, positive framing of self-views, the ratings of clinical participants demonstrated an orientation toward self-framing that was neither positive nor negative. Together, these novel findings shed light on the nature of self-appraisals in social anxiety. Implications of these results are discussed in terms of contemporary cognitive-behavioral models of social phobia.     

The challenge of raising ethical awareness: A case-based aiding system for use by computing and ICT students

Students, the future Information and Communication Technology (ICT) professionals, are often perceived to have little understanding of the ethical issues associated with the use of ICTs. There is a growing recognition that the moral issues associated with the use of the new technologies should be brought to the attention of students. Furthermore, they should be encouraged to explore and think more deeply about the social and legal consequences of the use of ICTs. This paper describes the development of a tool designed to raise students’ awareness of the social impact of ICTs. The tool offers guidance to students undertaking computing and computer-related courses when considering the social, legal and professional implications of the actions of participants in situations of ethical conflict. However, unlike previous work in this field, this tool is not based on an artificial intelligence paradigm. Aspects of the theoretical basis for the design of the tool and the tool’s practical development are discussed. Preliminary results from the testing of the tool are also discussed. An earlier version of this paper was presented by one of the authors at the First International Conference on Teaching Applied and Professional Ethics in Higher Education, Federal University of Surrey Centre for Applied Ethics, Southlands College, Roehampton, London, 2–4 September, 2003.     

Information processing biases and panic disorder: relationships among cognitive and symptom measures

To test cognitive models of panic disorder, a range of information processing biases were examined among persons with panic disorder (N=43) and healthy control participants (N=38). Evidence for automatic associations in memory was assessed using the Implicit Association Test, interference effects related to attention biases were assessed using a modified supraliminal Stroop task, and interpretation biases were assessed using the Brief Body Sensations Interpretation Questionnaire. In addition, the relationship between information processing biases and clinical markers of panic (including affective, behavioral, and cognitive symptom measures) was investigated, along with the relationships among biases. Results indicated more threat biases among the panic (relative to control) group on each of the information processing measures, providing some of the first evidence for an implicit measure of panic associations. Further, structural equation modeling indicated that the information processing bias measures were each unique predictors of panic symptoms, but that the bias indicators did not relate to one another. These findings suggest that cognitive factors may independently predict panic symptoms, but not covary. Results are discussed in terms of their support for cognitive models of panic and the potential for automatic versus strategic processing differences across the tasks to explain the low relationships across the biases.     

Violations of information structure: an electrophysiological study of answers to wh-questions

This study investigates brain responses to violations of information structure in wh-question-answer pairs, with particular emphasis on violations of focus assignment in it-clefts (It was the queen that silenced the banker). Two types of ERP responses in answers to wh-questions were found. First, all words in the focus-marking (cleft) position elicited a large positivity (P3b) characteristic of sentence-final constituents, as did the final words of these sentences, which suggests that focused elements may trigger integration effects like those seen at sentence end. Second, the focusing of an inappropriate referent elicited a smaller, N400-like effect. The results show that comprehenders actively use structural focus cues and discourse-level restrictions during online sentence processing. These results, based on visual stimuli, were different from the brain response to auditory focus violations indicated by pitch-accent [Hruska, C., Steinhauer, K., Alter, K., & Steube, A. (2000). ERP effects of sentence accents and violations of the information structure. In Poster presented at the 13th annual CUNY conference on human sentence processing, San Diego, CA.], but similar to brain responses to newly introduced discourse referents [Bornkessel, I., Schlesewsky, M., & Friederici, A. (2003). Contextual information modulated initial processes of syntactic integration: the role of inter- versus intrasentential predictions. Journal of Experimental Psychology: Learning, Memory and Cognition, 29, 871-882.].     

Delayed signal detection, differential reinforcement, and short-term memory in the pigeon.

In two discrete-trial delayed-detection experiments, six pigeons were trained on dependent concurrent variable-interval schedules. Pecking a red side key was reinforced when the brighter of two white lights (S1) had been presented on the center key, and pecking a green side key was reinforced when the duller of two white lights (S2) had been presented on the center key. Incorrect responses were red side-key pecks following S2 presentations and green side-key pecks following S1 presentations; these resulted in three-second blackouts. In Experiment 1, the time between presentation of S1 or S2 on the center key and the onset of the red and green side keys was varied nonsystematically from 0.06 seconds to 19.69 seconds across experimental conditions. Stimulus discriminability decreased as the stimulus-choice delay increased. A rectangular-hyperbolic function better described this decrease in discriminability over time than did a negative-exponential function. In Experiment 2, at each of three stimulus-choice delays (0.06, 3.85, and 10.36 seconds), relative reinforcer frequency for correct responses to the red and green side keys was varied by changing the values of the dependent concurrent variable-interval schedules. The sensitivity of choice to relative reinforcer frequency was independent of the decrease in stimulus discriminability with increasing stimulus-choice delay.     

Diverse groups and information sharing: The effects of congruent ties

The impact of congruence between social and knowledge ties on performance in diverse groups was examined. Congruence occurs when group members who are socially tied share the same information and a stranger has any unique information. Incongruence occurs when group members who are socially tied possess different information, and one of them shares information with a stranger. In Experiment 1, three-person groups with congruent social and knowledge ties utilized information more effectively, reported more effective group processes, and outperformed groups with incongruent ties. Experiment 2, which involved four-person groups, examined the role of congruence in groups with either a single minority information holder or two equal-sized subgroups. Congruent groups again outperformed incongruent groups, but this was only true when groups had a minority information holder. There was no difference in the performance of congruent and incongruent groups that had equal-sized subgroups. The implications of these findings for analyses of group composition and decision-making are discussed.     

Upbeat and happy: Arousal as an important factor in studying attention

The present study examined the effects of music-induced mood changes on different components of visual attention. Affective valence (positive vs. negative) and arousal (high vs. low) were manipulated by having participants listen to one of four versions of a Mozart Sonata that varied in mode (major or minor) and tempo (fast or slow). Attention was measured in three domains—alerting, orienting, and executive control. Affective valence and arousal had an effect on executive control, but not on alerting or orienting. Individuals who experienced positive valence had less efficient control over their responses than those who experienced negative valence, but only when arousal levels were high. Positive and negative valence did not influence executive control measures when arousal levels were low. These findings demonstrate that affective valence and arousal interact with one another to influence the processing of items in visual attention.