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91.
The visual environment is extremely rich and complex, producing information overload for the visual system. But the environment also embodies structure in the form of redundancies and regularities that may serve to reduce complexity. How do perceivers internalize this complex informational structure? We present new evidence of visual learning that illustrates how observers learn how objects and events covary in the visual world. This information serves to guide visual processes such as object recognition and search. Our first experiment demonstrates that search and object recognition are facilitated by learned associations (covariation) between novel visual shapes. Our second experiment shows that regularities in dynamic visual environments can also be learned to guide search behavior. In both experiments, learning occurred incidentally and the memory representations were implicit. These experiments show how top-down visual knowledge, acquired through implicit learning, constrains what to expect and guides where to attend and look. 相似文献
92.
Zusammenfassung. Das hier vorgestellte Modell lernt graduell, Planungsaufgaben aus der Klasse der Maschinenbelegungsprobleme (job-shop-scheduling problems) zu lösen. Mit Hilfe des Chunking-Mechanismus von Soar wird episodisches Wissen über die Belegungsreihenfolge von Aufträgen auf Maschinen memoriert. Bei der Entwicklung des Modells wurden zahlreiche qualitative (z. B. Transfereffekte) und quantitative Befunde (z. B. Bearbeitungszeiten) aus einer früheren empirischen Untersuchung berücksichtigt. In einer Validierungsstudie wurden dieselben Aufgaben von 14 Probanden und dem Modell bearbeitet. Die Passung von Simulationsdaten und empirischen Ergebnissen fiel insgesamt gut aus. Allerdings löst das Modell die Aufgaben schneller und zeigt auch einen etwas besseren Lernverlauf als die Probanden. Das Modell liefert eine Erklärung für das Rauschen, das typischerweise bei Bearbeitungszeiten zu beobachten ist: es handelt sich um erworbenes Wissen, das mehr oder weniger gut und auch unterschiedlich häufig auf neue Situationen übertragen wird. Der Lernverlauf der Probanden entspricht nur für aggregierte Daten einer Potenzfunktion (power law). Der vorgestellte Mechanismus zeigt, wie ein symbolisches Modell der Informationsverarbeitung graduelle Verhaltensänderungen generiert und wie der offensichtliche Erwerb allgemeiner Prozeduren ohne explizites Lernen von deklarativen Regeln erfolgen kann. Es wird nahegelegt, daß es sich hier um die Modellierung einer Form impliziten Lernens handelt. Summary. The model presented here gradually learns how to perform a job-shop scheduling task. It uses Soar's chunking mechanism to acquire episodic memories about the order to schedule jobs. The model was based on many qualitative (e.g., transfer effects) and quantitative (e.g., solution time) regularities found in previously collected data. The model was tested with new data where scheduling tasks were given to the model and to 14 subjects. The model generally fit these data with the restrictions that the model performs the task (in simulated time) faster than the subjects, and its performance improves somewhat more quickly than the subjects' performance. The model provides an explanation of the noise typically found in problem solving times - it is the result of learning actual pieces of knowledge that transfer more or less to new situations but rarely by an average amount. Only when the data are averaged (i.e., over subjects) does the smooth power law appear. This mechanism demonstrates how symbolic models can exhibit a gradual change in behavior and how the apparent acquisition of general procedures can be performed without resorting to explicit declarative rule generation. We suggest that this may represent a type of implicit learning. 相似文献
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Luc Steels 《Kognitionswissenschaft》1999,8(4):143-150
Linguistics must again concentrate on the evolutionary nature of language, so that language models are more realistic with respect to human natural languages and have a greater explanatory force. Multi-agent systems are proposed as a possible route to develop such evolutionary models and an example is given of a concrete experiment in the origins and evolution of word-meaning based on a multi-agent approach. 相似文献
96.
卫生资源优化配置的伦理要求 总被引:2,自引:0,他引:2
蒋广根 《医学与哲学(人文社会医学版)》1999,20(8):12-13
卫生资源是稀缺资源,卫生资源只有优化配置,才能达到我们的医学目的。卫生资源的优化配置的以公平为优先,坚持公平和效率相结合的原则。就目前所存在的和我们的医学目的不相适应的卫生资源配置方式的现状和主要问题进行分析,并提出了相应的改进方法。 相似文献
97.
Luke Robinson 《Philosophical Studies》2011,156(2):289-309
What are moral principles? In particular, what are moral principles of the sort that (if they exist) ground moral obligations or—at the very least—particular moral truths? I argue that we can fruitfully conceive of such principles as real, irreducibly dispositional properties of individual persons (agents and patients) that are responsible for and thereby explain the moral properties of (e.g.) agents and actions. Such moral dispositions (or moral powers) are apt to be the metaphysical grounds of moral obligations and of particular truths about what is morally permissible, impermissible, etc. Moreover, they can do other things that moral principles are supposed to do: explain the phenomena “falling within their scope,” support counterfactuals, and ground moral necessities, “necessary connections” between obligating reasons and obligations. And they are apt to be the truthmakers for moral laws, or “lawlike” moral generalizations. 相似文献
98.
科学发明创造中, 人们往往对一个问题百思不得其解, 但在看到某一启发性事物(原型)时, 突然产生顿悟, 继而发现解决问题的新思路。本研究以科学发明创造问题为实验材料, 采取“先呈现问题、后呈现原型”和“先呈现原型、后呈现问题”两种范式, 探讨问题解决中顿悟的原型位置效应, 并采用fMRI技术记录大脑的BOLD信号变化。结果发现:行为结果上, “问题在先”条件下正确率显著高于“原型在先”条件; 大脑激活结果上, 问题先导条件下的原型启发的大脑机制主要表现为左侧颞中回(left middle temporal gyrus)和左侧额中回(left middle frontal gyrus)的显著激活, “原型在先”条件下, 主要激活左侧扣带回(left cingulate gyrus)、左侧中央前回(left middle frontal gyrus)。 相似文献
99.
Why do people express moral outrage? While this sentiment often stems from a perceived violation of some moral principle, we test the counter-intuitive possibility that moral outrage at third-party transgressions is sometimes a means of reducing guilt over one’s own moral failings and restoring a moral identity. We tested this guilt-driven account of outrage in five studies examining outrage at corporate labor exploitation and environmental destruction. Study 1 showed that personal guilt uniquely predicted moral outrage at corporate harm-doing and support for retributive punishment. Ingroup (vs. outgroup) wrongdoing elicited outrage at corporations through increased guilt, while the opportunity to express outrage reduced guilt (Study 2) and restored perceived personal morality (Study 3). Study 4 tested whether effects were due merely to downward social comparison and Study 5 showed that guilt-driven outrage was attenuated by an affirmation of moral identity in an unrelated context. 相似文献
100.
Amori Yee Mikami Allison Jack Christina C. Emeh Haley F. Stephens 《Journal of abnormal child psychology》2010,38(6):721-736
We examined associations between children’s peer relationships and (a) their parents’ social competence as well as (b) their
parents’ behaviors during the children’s peer interactions. Participants were families of 124 children ages 6–10 (68% male),
62 with ADHD and 62 age- and sex-matched comparison youth. Children’s peer relationships were assessed via parent and teacher
report, and sociometric nominations in a lab-based playgroup. Parental characteristics were assessed via parent self-report
and observations of behavior during their child’s playgroup. After statistical control of relevant covariates, parents of
children with ADHD reported poorer social skills of their own, arranged fewer playdates for their children, and displayed
more criticism during their child’s peer interaction than did parents of comparison youth. Parents’ socialization with other
parents and facilitation of the child’s peer interactions predicted their children having good peer relationships as reported
by teachers and peers, whereas parental corrective feedback to the child and praise predicted poor peer relationships. Parents’
ratings of their child’s social skills were positively associated with ratings of their own social skills, but negatively
associated with criticism and facilitation of the child’s peer interactions. Relationships between parental behaviors and
peer relationships were stronger for youth with ADHD than for comparison youth. The relevance of findings to interventions
is discussed. 相似文献