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S Lewandowsky

Publications and source records attributed to S Lewandowsky.

8 recordsLinked to original sources
PubMed2000

A redintegration account of the effects of speech rate, lexicality, and word frequency in immediate serial recall.

Short-term serial recall performance is strongly affected by the nature of the items to be remembered. For example, memory span declines with decreasing speech rate (i.e., increasing pronunciation duration) of the items and, for a given speech rate, memory for non-words is poorer than for words. Similarly, words of high natural language frequency are recalled better than low-frequency words. Existing descriptive models have identified redintegration as underlying many of those effects. Redintegration refers to the process by which partially retrieved memorial information is converted into an overt response. This article presents a process model of redintegration based on a non-linear dynamic network, which is shown to handle the effects of speech rate, lexicality, and word frequency on memory span. Unlike previous descriptive efforts, the redintegration model also predicts the shape of the underlying serial position curves.

Humans↗
PubMed2000

A connectionist model of complacency and adaptive recovery under automation.

Automation is intended to reduce the demands on operators in complex environments, thereby enhancing overall system performance. Although automation usually reduces workload, it is often accompanied by a decline in monitoring performance, an effect known as complacency. The circumstances under which complacency occurs and how it can be prevented, for example by intermittently returning control to the operator, are empirically well understood. To date, that empirical knowledge has not been accompanied by strong psychological theory. This article presents a computational model of human performance under automation based on connectionist principles. The model is shown to explain several benchmark findings, among them the basic complacency effect; the effect of the variability of automation reliability on complacency; the effect of task complexity; and the effect of intermittently returning control to the operator.

Attention↗
PubMed2000

Competing strategies in categorization: expediency and resistance to knowledge restructuring.

The authors investigated people's ability to restructure their knowledge when additional information about a categorization task is revealed. In 2 experiments, people first learned to rely on a fairly accurate (but imperfect) predictor. At various points in training, a complex relationship between 2 other predictors was revealed in a schematic diagram that could support perfect performance. In Experiment 1, people adopted the complex strategy when it was revealed at the outset but were unable to restructure their knowledge after the expedient predictor had been learned. In Experiment 2, expedient knowledge persisted even with an adaptive display. The persistence of expedient knowledge is explained by associative blocking of potential alternative cues. A 3rd experiment analyzed the strategies people use with and without the diagram. The study confirmed that the diagram, when presented at the outset, significantly alters people's approach to the task.

Adolescent↗
PubMed2000

The dynamics of trust: comparing humans to automation.

Complex industrial environments involve cooperation between operators and automation. The strategies used to allocate tasks to automation are a crucial component of that cooperation and are known to be affected by the operators' trust in the automation. In 2 simulated process control experiments, the authors compared trust in automation with trust in human partners in equivalent situations. Experiment 1 found the relationship between trust and task allocation to be qualitatively identical, but quantitatively attenuated, for human partners as compared with automation. Experiment 2 additionally identified the operators' trustworthiness, as they thought it would be perceived by a human partner, as crucial to task allocation under human collaboration but not under automation. The results imply that human collaboration benefits from calibration of people's assessment of how others perceive them.

Adult↗
PubMed2000

Knowledge partitioning: context-dependent use of expertise.

Although exceptional performance is a defining attribute of expertise, experts sometimes exhibit striking errors and performance limitations. This article reports two experiments in which experts predicted the spread of bush fires, a domain characterized by complex but well-understood physical dynamics. Although accuracy was typically high, large errors were observed when two primary predictor variables were in opposition. In a second study, the experts' behavior--in contrast to that of novices--was additionally shown to depend on problem context. In one context, experts again committed errors, whereas in another, equally domain-relevant context, the correct predictions were made. Critically, when comparing performance across contexts, completely opposing predictions were made under identical physical conditions. We therefore suggest that expertise may comprise separate, and sometimes even mutually exclusive, components of knowledge.

Cognition↗
PubMed1999

Remote delivery of cognitive science laboratories: a solution for small disciplines in large countries.

Numerically small disciplines can be jeopardized by geographic difficulties, if student populations at universities are small and distances between them large. This problem could be addressed, if teaching resources could be shared among several universities and students in several locations could be taught simultaneously. We present the results of a trial in simultaneous Internet and videoconferencing delivery of an introductory cognitive science laboratory. The trial relied on off-the-shelf software and hardware. Students found the delivery nearly as effective as a locally run laboratory, despite a noticeable difference in the level of interactivity between the remote and other, local laboratory classes. We discuss possible further improvements in teaching efficiency and efficacy.

Cognitive Science↗
PubMed1993

Context effects in repetition priming are sense effects.

This article reports three experiments that investigate the role of context in repetition priming using a lexical decision task. The experiments show that repetition priming is either eliminated or significantly reduced if a change in context also alters the perceived sense of a nonhomographic target word. If perceived sense is not altered, a change in context is inconsequential. This points to the important role played by perceived sense in repetition priming. An explanation within a sense-specific activation framework is proposed in preference to a modified processing view.

Adult↗