Data‐driven approaches to information access

This paper summarizes three lines of research that are motivated by the practical problem of helping users find information from external data sources, most notably computers. The application areas include information retrieval, text categorization, and question answering. A common theme in these applications is that practical information access problems can be solved by analyzing the statistical properties of words in large volumes of real world texts. The same statistical properties constrain human performance, thus we believe that solutions to practical information access problems can shed light on human knowledge representation and reasoning.     

汉字词特征语义提取的实验研究

本研究运用语义判断的方法,对汉字词特征语义的提取做了初步的探讨,被试是28名大学生。实验结果表明,汉字形声字的义符在汉字词定义特征语义提取中有重要作用,在义符与词义一致时,能加速词的定义特征语义的提取。义符对词的特有特征的语义提取无作用,而特有特征的强度能很好地预测提取时间。本研究还发现,词的熟悉性和该词距其上属的语义距离对词的定义特征的语义提取亦有重要影响。     

语义联系类型和强度对预期推理生成的制约作用

首先采用开放式问卷实验方法,由被试生成日常生活中的事件以及组成这些事件的各种活动和活动的参加者。然后,对这些事件熟悉性、对活动的典型性和可区分性三个维度进行主观评价,形成事件以及每个事件活动序列,并据此编制实验材料。实验主要考察活动的典型性和可区分性对于熟悉性高的事件的预期推理的影响,以及不同工作记忆能力的被试进行事件预期推理时的加工模式。实验结果表明：（１）高工艺记忆能力的被试对事件的预期量小于     

Beyond the relational principle of reinforcement

Behavior under baseline conditions in which the contingency is absent can shed some light on the individual's performance under a schedule, but is insufficient as a basis for prediction of performance. This insufficiency of the baseline data runs counter to a recent formalization of the relational principle of reinforcement (Donahoe, 1977). A more satisfactory predictive model must incorporate not only the baseline level of the instrumental response and that of the contingent response, but also the schedule requirements, the character of each response in relation to the other, and the behavior required in simply switching from each to the other.     

Stimulus control of Pavlovian facilitation

Two experiments were conducted using an autoshaping procedure with pigeons to examine whether dimensional stimulus control by a Pavlovian facilitator parallels the control established following operant discrimination training. Facilitation training consisted of the presentation of a black vertical line on a white background as the B stimulus in a feature-positive discrimination in which the A stimulus (white keylight) was followed by grain presentation only if preceded by B. In this way, B facilitates or sets the occasion for pecking at A. Subsequent testing for generalization along the line-orientation dimension produced decremental gradients when the facilitation paradigm incorporated an explicit feature-negative stimulus (B−). These results parallel the decremental control obtained following operant discrimination training and suggest that Pavlovian facilitators and instrumental discriminative stimuli are functionally equivalent.     

词汇共现频率视角下语义联想效应及其神经机制

词汇识别与记忆受到词汇之间语义联想关系的影响。鉴于自由联想方法建立词汇语义联想关系的局限性, 研究者们提出用共现联想法建立词汇之间的语义联想关系。本文对词汇共现频率视角下的语义联想效应及其神经机制的研究进行分析发现, 语义联想的丰富程度和关联程度影响词汇的加工; 与少语义联想词相比, 多语义联想词导致P200波幅增大和N400波幅减小; 语义联想加工涉及的脑区主要是额上回和左内侧颞叶区域。未来研究需要探讨自由联想法和共现联想法建立语义联想关系的差异, 基于共现联想法进一步地探究语义联想的行为规律和神经机制, 并从共现联想的角度开展汉语语义联想效应及神经机制的研究。     

象似性和手语学习经验对中国手语-汉语跨模态语义启动效应的影响

采用启动条件下的词汇判断任务,考察熟练手语使用者和无手语经验成年听人的跨模态语义启动效应。结果发现：1)在象似词条件下,两组被试判断汉语语义相关词的反应时均快于语义无关词,说明手语象似词和汉语词之间存在跨模态语义启动效应。2)在非象似词条件下,仅手语熟练被试判断汉语语义相关词的反应时快于语义无关词,无手语经验被试判断汉语语义相关词和无关词的速度没有差异。这是由于前者心理词库中的手语词和口语词共享语义表征,而后者主要依赖手语象似词的视觉模拟性。整个研究表明,中国手语和汉语间存在跨模态语义启动效应,但该效应受到手语词象似性和手语学习经历的调节。     

Metasemantic ethics

The idea that experts (especially scientific experts) play a privileged role in determining the meanings of our words and the contents of our concepts has become commonplace since the work of Hilary Putnam, Tyler Burge, and others in the 1970s. But if experts have the power to determine what our words mean, they can do so responsibly or irresponsibly, from good motivations or bad, justly or unjustly, with good or bad effects. This paper distinguishes three families of metasemantic views based on their attitudes towards bad behaviour by meaning-fixing experts, and draws a series of distinctions relevant for the normative evaluation of meaning-determining actions.     

The effects of mood and retrieval cues on semantic memory and metacognition

We investigated whether the previously established effect of mood on episodic memory generalizes to semantic memory and whether mood affects metacognitive judgments associated with the retrieval of semantic information. Sixty-eight participants were induced into a happy or sad mood by viewing and describing IAPS images. Following mood induction, participants saw a total of 200 general knowledge trivia items (50 open-ended and 50 multiple-choice after each of two mood inductions) and were asked to provide a metacognitive judgment about their knowledge for each item before providing a response. A sample trivia item is: Author – – To kill a mockingbird. Results indicate that mood affects the retrieval of semantic information, but only when the participant believes they possess the requested semantic information; furthermore, this effect depends upon the presence of retrieval cues. In addition, we found that mood does not affect the likelihood of different metacognitive judgments associated with the retrieval of semantic information, but that, in some cases, having retrieval cues increases accuracy of these metacognitive judgments. Our results suggest that semantic retrieval processes are minimally susceptible to the influence of affective state but does not preclude the possibility that affective state may influence encoding of semantic information.     

Age-Specific Effects of Lexical–Semantic Networks on Word Production

The lexical–semantic organization of the mental lexicon is bound to change across the lifespan. Nevertheless, the effects of lexical–semantic factors on word processing are usually based on studies enrolling young adult cohorts. The current study aims to investigate to what extent age-specific semantic organization predicts performance in referential word production over the lifespan, from school-age children to older adults. In Study 1, we conducted a free semantic association task with participants from six age-groups (ranging from 10 to 80 years old) to compute measures that capture age-specific properties of the mental lexicon across the lifespan. These measures relate to lifespan changes in the Available Richness of the mental lexicon and in the lexical–semantic Network Prototypicality of concrete words. In Study 2, we used the collected data to predict performance in a picture-naming task on a new group of participants within the same age-groups as for Study 1. The results show that age-specific semantic Available Richness and Network Prototypicality affect word production speed while the semantic variables collected only in young adults do not. A richer and more prototypical semantic network across subjects from a given age-group is associated with faster word production speed. The current results indicate that age-specific semantic organization is crucial to predict lexical–semantic behaviors across the lifespan. Similarly, these results also provide cues to the understanding of the lexical–semantic properties of the mental lexicon and to lexical selection in referential tasks.