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91.
We present a simple but effective method based on Luce’s choice axiom [Luce, R.D. (1959). Individual choice behavior: A theoretical analysis. New York: John Wiley & Sons] for consistent estimation of the pairwise confusabilities of items in a multiple-choice recognition task with arbitrarily chosen choice-sets. The method combines the exact (non-asymptotic) Bayesian way of assessing uncertainty with the unbiasedness emphasized in the classical frequentist approach.We apply the method to data collected using an adaptive computer game designed for prevention of reading disability. A player’s estimated confusability of phonemes (or more accurately, phoneme-grapheme connections) and larger units of language is visualized in an easily understood way with color cues and explicit indication of the accuracy of the estimates. Visualization of learning-related changes in the player’s performance is considered.The empirical validity of the choice axiom is evaluated using the game data itself. The axiom appears to hold reasonably well although a small systematic violation is observable for the smallest choice-set sizes.  相似文献   
92.
用问卷法对194名初中生学业延迟满足的特点及相关因素进行了研究。结果表明:初中学生的学业延迟满足存在年级和性别差异,初二和初三学生的学业延迟满足水平明显低于初一学生,女生比男生的学业延迟满足能力高。课堂目标结构与学业延迟满足有显著关系,任务取向的课堂目标与学业延迟满足呈正相关关系;自我取向的课堂目标与学业延迟满足呈负相关关系。任务价值、自我效能与学业延迟满足呈正相关关系,学业延迟满足与学业成绩呈正相关关系。  相似文献   
93.
The work-hardening behaviour of virgin martensitic steel has been investigated in a strictly un-aged state and after various ageing conditions. At room temperature (RT), the un-aged alloy shows astonishing tensile performances (ultimate tensile stress?=?1600?MPa/uniform elongation?=?15%) but unexpected serrations. These serrations can be suppressed by static ageing (at RT or higher) while maintaining the initial work-hardening rate (ageing at RT). Parallel investigations using atom probe tomography reveal that the distribution of carbon at the atomic scale evolves from purely homogeneous for virgin martensite to partly segregated at a very fine scale (5–10?nm) after static ageing. This particular mechanical behaviour can therefore be associated with a very local decrease in available carbon in solid solution due to redistribution and segregations on defects (nanotwins) that occurs rapidly, even after few days at RT.  相似文献   
94.
The effects of crystallization on the electron work function and corrosion resistance of Zr65Al7.5Cu17.5Ni10 amorphous alloys have been studied. The single-phase amorphous alloy exhibits a better corrosion resistance and has a higher work function than the partially and fully crystallized alloys with the same composition. The close relationship between corrosion resistance and work function indicates that the Kelvin probe technique can be a powerful tool for characterizing the corrosion behaviour of amorphous alloy on an electronic level.  相似文献   
95.
Two experiments using the interference paradigm are reported. In the first experiment, the participants spoke aloud the names of celebrities and the names of objects when presented with pictures while hearing distractors. In the case of proper names, we replicated the data obtained by Izaute and Bonin (2001) using the interference paradigm with a proper name written naming task. In the case of common names, the results replicated those obtained by Shriefers, Meyer, and Levelt (1990). In the second experiment, the participants produced the names of celebrities when presented with their faces while hearing distractors that were either proper names associated with the celebrities (associate condition), that belonged to a different professional category (different condition), or that corresponded to the proper names of the celebrities (identical condition). For negative SOAs, “associate” distractors were found to increase latencies compared to the “different category” condition. The implications of the findings for proper name retrieval are briefly discussed.  相似文献   
96.
Diagnosis of Alzheimer's disease (AD) requires evidence of progressive decline in cognitive function. However, many tests used to assess cognitive function suffer from considerable practice effects, reducing their reliability. Several studies have reported that the ability to do two things at once, or dual tasking, is impaired in AD, but unaffected by healthy ageing. The apparent specificity of this impairment suggests that this assessment may be particularly useful in the early diagnosis of AD, but the reliability of this assessment remains unknown. Therefore, this study investigated simultaneous performance of digit recall and tracking tasks across six testing sessions in eight people with AD, eight healthy older adults and eight healthy younger adults. The results found that dual-task performance was unaffected by healthy ageing, but significantly impaired in AD, with no effect of repeated exposure. The absence of any improvements in performance despite increased familiarity with the task's demands suggests that not only is the dual-task assessment well suited for monitoring progression over time, but also that dual tasking involves a specific cognitive function which is impaired in the AD brain.  相似文献   
97.
Many reports have described a survival judgment task that requires participants to judge words according to their relevance to a survival situation, eliciting better recall than that obtained in other judgment tasks (e.g., semantic or self‐judgment tasks). Two explanatory hypotheses (the adaptive hypothesis and the elaboration hypothesis) have been proposed. Here we used the memory load paradigm to investigate whether the adaptive hypothesis or the combination hypothesis can better account for the memory enhancement of the survival judgment task. We used a survival judgment task and an autobiographical recall task with the condition of no memory load or memory load. The 48 participants performed four encoding conditions (memory load—survival, no memory load—survival, memory load—autobiographical, and no memory load—autobiographical). The results showed that memory enhancement of the survival judgment task occurred only in the no memory load condition, but not in the memory load condition. Our results support the elaboration hypothesis. We also discuss the validity of the elaboration hypothesis and future directions to be pursued in this research field.  相似文献   
98.
In the present study, event-related brain potentials (ERPs) were applied to the study of language comprehension in the Italian language. The ERPs were recorded from 10 electrodes while the participants read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic anomalies. Final words that were inconsistent with the sentence context elicited a negative wave at about 400 ms poststimulus that was more concentrated in the posterior sites of the scalp, whereas final words that were incongruous with the grammatical structure (subject-verb nonagreement) elicited a positive wave at about 600 ms poststimulus that was homogeneously distributed on the scalp. The authors found no differences based on the perceptual modality of the stimulus (visual or auditory), nor did they find different ERP correlates as a function of task relevance (explicit-implicit task induction). The available evidence indicated that the ERP response to semantic anomalies was at least partially distinct from the ERP response to syntactic anomalies, and that a syntactic parser is a plausible process included in sentence comprehension. The two semantic and syntactic effects appear as automatic processes of the decoding of the anomalies and also modality-independent processes. Cross-linguistic applications are considered in the general discussion.  相似文献   
99.
Two experiments employed Potential Performance Theory (PPT) to correct for inconsistency in a speeded task. In Experiment 1, a search task was employed whereby participants searched for a target letter among distracters. In Experiment 2, the search task was more complex and naturalistic—participants searched for enemy weapons in aerial photographs. Not surprisingly, the results revealed that longer search times led to greater accuracy. However, this improvement was due only in part to improved search strategies. Much, if not most, of the improvement was due to increased consistency. The authors demonstrate and discuss some of the advantages to be gained by considering a speeded task within the context of a clear and mathematically precise theory (PPT).  相似文献   
100.
Although the Serial Reaction-Time Task has been an effective tool in studying procedural learning, there is still a debate as to whether learning in the task is effector-based, stimulus-based, or response-based. In this article, the authors contribute to this debate by contrasting response- and stimulus-based learning by manipulating them selectively and simultaneously. Results show that (a) participants learned response sequences in the absence of stimulus-specific perceptual sequence information but (b) not stimulus sequences without corresponding response information. In a third condition, response sequence and stimulus frequency information were in conflict, and each effect decreased learning in the other domain. Overall, our findings show that learning in these tasks is primarily motor-based, but it is also constrained by relatively salient perceptual information. Together with earlier findings in the literature, the findings also suggest a task and stimulus-arrangement-specific interaction between motor and perceptual learning, where relevance and salience of the specific information plays a crucial role.  相似文献   
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