David Peebles‎ > ‎

Abstracts

Strategy and pattern recognition recognition in expert comprehension of 2 x 2 interaction graphs

Peebles, D. (in press)

I present a model of expert comprehension performance for 2 × 2 "interaction" graphs typically used to present data from two-way factorial research designs. Developed using the ACT-R cognitive architecture, the model simulates the cognitive and perceptual operations involved in interpreting interaction graphs and provides a detailed characterisation of the information extracted from the diagram, the prior knowledge required to interpret interaction graphs, and the knowledge generated during the comprehension process. The model produces a scan path of attention fixations and a symbolic description of the interpretation which can be compared to human eye movement and verbal protocol data respectively, provides an account of the strategic processes that control comprehension, and makes explicit what underlies the differences between expert and novice performance.

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The effect of Gestalt laws of perceptual organisation on the comprehension of three-variable bar and line graphs

Ali, N. & Peebles, D. (in press)

Objective. We report three experiments investigating the ability of undergraduate college students to comprehend 2x2 'interaction' graphs from two-way factorial research designs.
Background.; Factorial research designs are an invaluable research tool widely used in all branches of the natural and social sciences and the teaching of such designs lies at the core of many college curricula. Such data can be represented in bar or line graph form. Previous studies have shown however that people interpret these two graphical forms differently.
Method. In Experiment 1 participants were required to interpret interaction data in either bar or line graphs while thinking aloud. Verbal protocol analysis revealed that line graph users were significantly more likely to misinterpret the data or fail to interpret the graph altogether.
Results. The patterns of errors line graph users made were interpreted as arising from the operation of Gestalt principles of perceptual organisation and this interpretation was used to develop two modified versions of the line graph which were then tested in two further experiments. One of the modifications resulted in a significant improvement in performance.
Conclusion. Results of the three experiments support the proposed explanation and demonstrate the effects (both positive and negative) of Gestalt principles of perceptual organisation on graph comprehension.
Application. We propose that our new design provides a more balanced representation of the data than the standard line graph for non-expert users to comprehend the full range of relationships in two-way factorial research designs and may therefore be considered a more appropriate representation for use in educational and other non-expert contexts.

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A cognitive architecture-based model of graph comprehension

Peebles, D. (2012)

I present a model of expert comprehension performance for 2x2 'interaction' graphs typically used to present data from two-way factorial research designs. Developed using the ACT-R cognitive architecture, the model simulates the cognitive and perceptual operations involved in interpreting interaction graphs and provides a detailed characterisation of the information extracted from the diagram, the prior knowledge required to interpret interaction graphs, and the knowledge generated during the comprehension process. The model produces a scan path of attention fixations and a symbolic description of the interpretation which can be compared to human eye movement and verbal protocol data respectively, provides an account of the strategic processes that control comprehension, and makes explicit what underlies the differences between expert and novice performance.

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Making audience experiences more meaningful and emotionally engaging through mixed visual and audio media

Bonner, J., Ramduny-Ellis, D., & Peebles, D. (2012)

Unlike a conventional lecture, where interaction and delivery behaviour is generally predictable, this paper presents suggestions for alternative and innovative delivery methods using different forms of visual and auditory modes to create a 'performance lecture'. A performance lecture is distinct from a conventional lecture in several ways. Its primary purpose is not simply to impart knowledge didactically, but to find ways of making spectatorship emotionally engaging. This paper first discusses the constituent parts of our evolving framework for performance lectures. We then provide a review of some initial visually-based demonstrator work, a 12 minute 'triptych' demonstrator video, followed by some preliminary analysis of a user evaluation study. Suggestions for further work conclude this paper.

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The different effects of thinking aloud and writing on graph comprehension

Ali, N. & Peebles, D. (2011)

We report an experiment which seeks to determine how novice users' conceptual understanding of graphs differs depending on the nature of the interaction with them. Undergraduate psychology students were asked to interpret three-variable "interaction" data in either bar or line graph form and were required to either think aloud while doing so or to produce written interpretations. Analysis of the verbal protocols and written interpretations showed that producing a written interpretation revealed significantly higher levels of comprehension than interpreting them while thinking aloud. Specifically, a significant proportion of line graph users in the verbal protocol condition was either unable to interpret the graphs, or misinterpreted information presented in them. The occurrence of these errors was substantially lower for the bar graph users in the verbal protocol condition. In contrast, analysis of the written condition revealed no significant difference in the level of comprehension between the two graph types. Possible explanations for these findings are discussed.

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Modelling dynamic decision making with the ACT-R cognitive architecture

Peebles, D. & Banks, A. P. (2010)

This paper describes a model of dynamic decision making in the Dynamic Stocks and Flows (DSF) task, developed using the ACT-R cognitive architecture. This task is a simple simulation of a water tank in which the water level must be kept constant whilst the inflow and outflow changes at varying rates. The basic functions of the model are based around three steps. Firstly, the model predicts the water level in the next cycle by adding the current water level to the predicted net inflow of water. Secondly, based on this projection, the net outflow of the water is adjusted to bring the water level back to the target. Thirdly, the predicted net inflow of water is adjusted to improve its accuracy in the future. If the prediction has overestimated net inflow then it is reduced, if it has underestimated net inflow it is increased. The model was entered into a model comparison competition-the Dynamic Stocks and Flows Challenge-to model human performance on four conditions of the DSF task and then subject the model to testing on five unseen transfer conditions. The model reproduced the main features of the development data reasonably well but did not reproduce human performance well under the transfer conditions. This suggests that the principles underlying human performance across the different conditions differ considerably despite their apparent similarity. Further lessons for the future development of our model and model comparison challenges are considered.

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Spaces or Scenes: Map-based Orientation in Urban Environments

Davies, C. & Peebles, D. (2010)

Two experiments examined people's strategies when orienting with a map in outdoor scenes within unfamiliar urban environments. We investigated how the 3D visual scene and the 2D layout geometry influenced people's choices of features when matching the scene and the map, and studied the problems they encountered when doing so. Results support previous evidence that in geographically realistic contexts, visible salient landmarks bias people away from using optimal geometry-matching strategies. This implies that prediction of orientation difficulty merely from analysing the spatial layout (e.g., with space syntax isovist measures) may be highly problematic. Implications for future map design are discussed.

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Differences in comprehensibility between three-variable bar and line graphs

Peebles, D. & Ali, N. (2009)

We report an experiment investigating graph comprehension. Verbal protocol data were collected while participants attempted to understand six bar or line graphs representing relationships between three variables. Analysis of the verbal protocols revealed significant differences in the level of comprehension between the two graph types. Specifically, a significant proportion of line graph users was either unable to interpret the graphs, or misinterpreted information presented in them. These errors did not occur in the bar graph condition. The difference is explained in terms of the high salience of the lines in line graphs which hinders the correct or full interpretation of the relationships depicted. The results of the experiment provide a strong rationale for the use of bar graphs to display such three-variable data sets, particularly for a general audience.

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The effect of emergent features on judgments of quantity in configural and separable displays

Peebles, D. (2008)

Two experiments investigated effects of emergent features on perceptual judgments of comparative magnitude in three diagrammatic representations: kiviat charts, bar graphs and line graphs. Experiment 1 required participants to compare individual values whereas in Experiment 2 participants had to integrate several values to produce a global comparison. In Experiment 1 emergent features of the diagrams resulted in significant distortions of magnitude judgments, each related to a common geometric illusion. Emergent features are also widely believed to underlie the general superiority of configural displays such as kiviat charts for tasks requiring the integration of information. Experiment 2 tested the extent of this benefit using diagrams with a wide range of values. Contrary to the results of previous studies, the configural display produced the poorest performance compared to the more separable displays. Moreover, the pattern of responses suggests that kiviat users switched from an integration strategy to a sequential one depending on the shape of the diagram. The experiments demonstrate the powerful interaction between emergent visual properties and cognition and reveal limits to the benefits of configural displays for integration tasks.

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Effects of geometry, landmarks and orientation strategies in the 'drop-off' orientation task.

Peebles, D., Davies, C., and Mora, R. (2007)

Previous work is reviewed and an experiment described to examine the spatial and strategic cognitive factors impacting on human orientation in the 'drop-off' static orientation scenario, where a person is matching a scene to a map to establish directional correspondence. The relative roles of salient landmarks and scene content and geometry, including space syntax isovist measures, are explored both in terms of general effects, individual differences between participant strategies, and the apparent cognitive processes involved. In general people tend to be distracted by salient 3D landmarks even when they know these will not be detectable on the map, but benefit from a salient 2D landmark whose geometry is present in both images. However, cluster analysis demonstrated clear variations in strategy and in the relative roles of the geometry and content of the scene. Results are discussed in the context of improving future geographic information content.

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Strategies for orientation: The role of 3D landmark salience and map alignment.

Davies, C., & Peebles, D. (2007)

An experiment and eye movement study investigated the strategies people use to orientate themselves in urban settings using a streetmap. Previous studies have suggested that the preferred strategy involves choosing salient landmarks to match between the scene and the map. We presented stimuli for which single-landmark matching was not the optimal strategy; the only unambiguous information available for matching was the map's 2D geometry which could also be abstracted from the scene. However, most participants still chose a landmark-based strategy. We discuss the implications for cognitive models, for understanding individual differences, and for potentially improving map designs to aid orientation.

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Sorting preference in children with autism: The dominance of concrete features.

Ropar, D., & Peebles, D. (2007)

The current study investigates preference to sort objects on the basis of either concrete or abstract features in children with and without autism. Participants were asked to sort a set of books into two groups that could be differentiated according to concrete (color, size) or abstract criteria (category membership: sports/games). The results showed that those with autism, unlike controls, were significantly more likely to sort according to a concrete criterion. In a further phase of testing, those with autism still did not sort according to abstract criteria, even when this was the only basis for sorting systematically. The findings are interpreted as evidence for a preference in autism to process concrete over abstract features of stimuli.

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Isovists for Orientation: Can space syntax help us predict directional confusion?

Davies, C., Mora, R. and Peebles, D. (2006)

Focusing on its lessons for deriving and using space syntax measures, particularly those related to isovists, this paper explores the potential for identifying spatial predictors of people's orientation performance with a map. Matching a map to a visible scene, to decide in which direction one is facing, is argued to be a fundamental cognitive subtask which arises in a number of contexts beyond mere wayfinding. The challenge for space syntax is to supply readily computed measures that can adequately predict where this task is more difficult than average, based on analysing a 2D map. If this can be achieved then spaces may be automatically assessed for potential orientation difficulty, so that both the map and the environment can be enhanced to include cues to make it easier. We discuss some issues that arise in applying space syntax to this situation, and describe current progress towards this goal.

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Modelling Interactive Behaviour with a Rational Cognitive Architecture.

In this chapter we discuss a number of recent studies that demonstrate the use of rational analysis (Anderson, 1990) and cognitive modelling methods to understand complex interactive behaviour involved in three tasks: (1) icon search, (2) graph reading, and (3) information retrieval on the World Wide Web (WWW). We describe the underlying theoretical assumptions of rational analysis and the adaptive control of thought-rational (ACT-R) cognitive architecture (Anderson \& Lebiere, 1998), a theory of cognition that incorporates rational analysis in its mechanisms for learning and decision making. In presenting these studies we aim to show how such methods can be combined with eye movement data to provide detailed, highly constrained accounts of user performance that are grounded in psychological theory. We argue that the theoretical and technological developments that underpin these methods are now at a stage that the approach can be more broadly applied to other areas of Web use.

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Modelling performance in the Sustained Attention to Response Task. Proceedings of the Sixth International Conference on Cognitive Modeling. Mahwah, NJ: Lawrence Erlbaum.

Peebles, D., & Bothell, D. (2004)

We present a computational model of human performance on the Sustained Attention to Response Task, a computer-based task in which people must withhold responses to infrequent and unpredictable stimuli during a period of rapid and rhythmic responding to frequent stimuli. The model, formulated within the ACT-R cognitive architecture, accounts for human performance in terms of two competing strategies and the dynamic modification of priorities given competing task demands to minimise both response time and error. The model suggests that such strategic factors may be responsible for the observed speed-accuracy trade-off rather than the alternative proposal based on sustained attention.

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Distortions of perceptual judgement in diagrammatic representations. Proceedings of the Twenty Sixth Annual Conference of the Cognitive Science Society. Mahwah, NJ: Lawrence Erlbaum.

Peebles, D. (2004)

An experiment is reported which investigates the distorting effects of various graphical features in three different diagrammatic representations of the same information. The experiment revealed significant distortions in users' perceptual judgements of distance both between the different diagrams and within each diagram. The results of the experiment are interpreted as indicating the crucial role of anchor points such as axis tick marks along dimensions.

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Modelling the effect of task and graphical representation on response latency in a graph reading task.

Peebles, D., & Cheng, P. C.-H. (2003)

We report a detailed investigation into the cognitive, perceptual and motor processes involved in the performance of a common graph reading task using different types of Cartesian co-ordinate graphs. We describe an experiment in which participants' eye movements were recorded while they carried out the task, the results of which show that the assumption of optimal scan paths employed in the task analysis serves as an approximation which obscures the detailed sequences of saccades made by individuals. The research also provides a clear demonstration of the computational inequivalence of two sets of informationally equivalent graphs and illustrates how the computational advantages of a representation for certain tasks can outweigh other factors such as user unfamiliarity. We then present two cognitive models of the experiment using the ACT-R/PM cognitive architecture which replicate the pattern of observed response latencies for the experiment conditions and account for the complex scan paths revealed by the eye movement study. From the research we generate three guidelines for visual display and graphical user interface design: (a) that designers should consider not only alternative representational formats but also how different quantities are encoded within any chosen format (b) that designers should consider the full range of alternative varieties of a given task in relation to the form of a representation, (c) designers should attempt to balance the cost of familiarisation with the computational advantages of less familiar representations. The research also demonstrates the value of computational modelling in accounting for the cognitive factors underlying reasoning with complex external representations, matching complex patterns of eye movements, and providing testable predictions of the times to carry out individual tasks.

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Extending task analytic models of graph-based reasoning: A cognitive model of problem solving with Cartesian graphs in ACT-R/PM.

Peebles, D., & Cheng, P. C.-H. (2002)

Models of graph-based reasoning have typically accounted for the variation in problem solving performance with different graph types in terms of a task analysis of the problem relative to the particular visual properties of each graph type (e.g. Lohse, 1993; Peebles, Cheng & Shadbolt 1999, submitted). This approach has been used to explain response time and accuracy differences in experimental situations where data are averaged over experimental conditions. An experiment is reported in which participants' eye movements are recorded while they were solving various problems with different graph types. The eye movement data revealed fine grained fixation patterns that are not captured by current analyses based on optimal fixation sequences. It is argued that these patterns reveal the effects of working memory limitations during the time course of problem solving. An ACT-R/PM model of the experiment is described in which a similar pattern of eye fixations is produced as a natural consequence of the decay in activation of perceptual chunks over time.

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Graph-based reasoning: From task analysis to cognitive explanation.

Peebles, D., & Cheng, P. C.-H. (2001)

Models of graph-based reasoning have typically accounted for the variation in problem solving performance with different graph types in terms of a task analysis of the problem relative to the particular visual properties of each graph type (e.g. Lohse, 1993; Peebles, Cheng & Shadbolt 1999, submitted). This approach has been used to explain response time and accuracy differences in experimental situations where data are averaged over experimental conditions. A recent experiment is reported in which participants' eye movements were recorded while they were solving various problems with different graph types. The eye movement data revealed fine grained scanning and fixation patterns that are not predicted by standard task analytic models. From these eye-movement studies it is argued that there is a missing level of detail in current task analytic models of graph-based reasoning.

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Extending task analytic models of graph-based reasoning: A cognitive model of problem solving with Cartesian graphs in ACT-R/PM.

Peebles, D., & Cheng, P. C.-H. (2001)

Models of graph-based reasoning have typically accounted for the variation in problem solving performance with different graph types in terms of a task analysis of the problem relative to the particular visual properties of each graph type (e.g. Lohse, 1993; Peebles, Cheng & Shadbolt 1999, submitted). This approach has been used to explain response time and accuracy differences in experimental situations where data are averaged over experimental conditions. An experiment is reported in which participants' eye movements are recorded while they were solving various problems with different graph types. The eye movement data revealed fine grained fixation patterns that are not captured by current analyses based on optimal fixation sequences. It is argued that these patterns reveal the effects of working memory limitations during the time course of problem solving. An ACT-R/PM model of the experiment is described in which a similar pattern of eye fixations is produced as a natural consequence of the decay in activation of perceptual chunks over time.

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Multiple processes in graph-based reasoning.

Peebles, D., Cheng, P. C.-H., & Shadbolt, N. (1999)

Current models of graph understanding typically address the encoding and interpretive processes involved during the course of comprehension and largely focus on the visual properties of the graph. An experiment comparing reasoning with two types of graph is presented. On the basis and scope of existing models, performance with the two graphs would not be predicted to differ substantially. The are substantial computational differences between the graphs, however. It is suggested, therefore, that an adequate model of graph use must incorporate different combinations of visual properties of the graphs, levels of graph complexity, interpretive schemas and task requirements.

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Compiling ontologies into structured views and interviews: The design of a graph drawing tool for knowledge elicitation.

Cupit, J., Shadbolt, N., Cheng, P. C.-H., & Peebles, D. (1999)

In this paper we consider how the methodological power of ontologies can best be delivered to knowledge engineers by supporting practical knowledge elicitation. Pre-specified ontologies can provide the basis for the design of structured knowledge elicitation interviews and supportive knowledge elicitation tools. However, for this purpose, attention to ontologies and knowledge-re-use strategies alone cannot suffice; attention to the semiotics of representational media used for model building is important as well. This claim is backed by the analysis of the affordances and properties of Cartesian Graphs within an ontology-minded framework. We shall also examine how such considerations affect the functional specification and architectural design of knowledge modeling environments. We argue that, whilst providing general modeling tools that support knowledge editing under ontological constraint is important, this is only part of the problem. For a model-building tool to be effective, there must be guidance through the model-building process. We present an architecture that directly addresses this issue with semiotic considerations in mind. The potential of ontology-based KA is realised through the provision of highly context-sensitive advice and guidance for building representations. This is illustrated by a tool designed to support Cartesian graph drawing as a knowledge elicitation technique.

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A connectionist model of categorization response times.

Peebles, D., & Lamberts, K. (1999)

Although perceptual categorization has been studied extensively in psychology, response times in categorization tasks have only recently become an important research topic. In this article, we propose a connectionist model of categorization RT, called CONCAT, which aims to provide a joint account of response times and choice proportions in binary classification tasks. First, we outline the basic principles of the model. Next, we present a perceptual categorization experiment and apply CONCAT to the results.

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The effect of stimulus frequency on classification accuracy and response time. Unpublished doctoral dissertation. University of Birmingham, Birmingham, 1997.

Peebles, D. (1997).

Recent research in categorisation has focused upon the investigation of response time (RT) and the development of existing formal models to account for data from speeded classification experiments. The research reported here examines the alternative theories of categorisation RT and compares two current models, the Exemplar Based Random Walk model (EBRW; Nosofsky and Palmeri, 1997) and the Extended Generalised Context Model (EGCM; Lamberts, 1995, in press, submitted) in a series of experiments. In addition, a new model of categorisation RT is proposed, ALCOVE(RT), based on Kruschke’s (1992) connectionist ALCOVE model of category learning, and tested. This thesis also attempts to resolve a current debate in the categorisation literature by investigating the effect of stimulus frequency on categorisation performance. The results of the research provide strong evidence for the effect of stimulus frequency on both classification accuracy and RT and show that accurate predictions of these performance measures cannot be based solely on information relating to the abstract category structure.

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