This article reviews research on the use of situation models in lnguage comprehension and memory retrieval over the past 15 years. Situation models are integrated mental representations of a described state of affairs. Significant progress has been made in the scientific understanding of how situation models are involved in language comprehension and memory retrieval. Much of this research focuses on establishing the existence of situation models, often by using tasks that assess one dimension of a situation model. However, the authors argue that the time has now come for researchers to begin to take the multidimensionality of situation models seriously. The authors offer a theoretical framework and some methodological observations that may help researchers to tackle this issue.

this paper we will argue that task knowledge structures are functionally equivalent to the knowledge structures that people possess and use when performing a task. We then go on to describe a method for identifying, analysing and modelling task knowledge structures (TKS). The contents of these TKS models can be usefully applied to the generation of design solutions. A method for applying these models to design is described. In describing TKS models and their application to design we will use examples taken from real tasks that have been analysed and real designs that have been proposed. However, because these examples are taken from complex domains we have selected them so that they will exemplify our approach rather than as complete models of the tasks within the domains

This article reports on a study that investigates how older adolescents cognitively utilize information on the drug, heroin. With a small group of four girls in their final year of secondary education, the study sought to: (a) establish the perceived effects of exposures to information; (b) establish how the perceived effects are associated with changes to the girls ’ knowledge structures; and (c) establish any patterns in relation to changes in knowledge structures and perceived effects. The study employed a quasi-experimental, repeated-phase approach. The girls ’ existing knowledge structures about the drug, heroin, were elicited and mapped, as were knowledge structures after each of three exposures to different information on heroin. The knowledge structures after each exposure were shown to change by cognitive strategies of appending, inserting, and deleting. Five types of effects, as types of cognitive information utilization, were identified, these being: Get a complete picture, get a changed picture, get a clearer picture, get a verified picture, and get a position in a picture. The study also showed that there was coherence between the effects and how these effects were manifested in changes to the girls ’ knowledge structures. This article also discusses important implications for information practice and instructional design.

Interaction. Please do not cite or circulate without permission from the authors. A computer system does not itself express the motivations that initiated its design, the user requirements it was intended to address, the discussions, debates and negotiations that determined its organization, the reasons for its particular features, the reasons against features it does not have, the weighing of tradeoffs, and so forth. This information comprises the design rationale of the system. It can be critical to the many stakeholders in a design process: customers, users, service providers, and marketers, as well as designers who want to build upon the system and the ideas it embodies. Design rationale can contribute to theory development in HCI in three ways. First, it provides a foundation for ecological science in HCI by describing the decisions and implicit causal relationships embodied in HCI artifacts. Second, it provides a foundation for action science in HCI by integrating activities directed at description and understanding with those directed at design and development. Finally, it provides a framework for a synthetic science of HCI in which the insights and predictions of diverse technical theories can be integrated. The preceding chapters illustrated how theoretical concepts and methods from a variety of sciences are used to gain insight in the context of HCI design and evaluation. This chapter inverts that train of thought to some extent. It shows how reflective HCI design practices — involving design rationale documentation and analysis — can be used (1) to closely couple theoretical concepts and methods with the designed artifacts that instantiate them, (2) to more closely integrate theory application and theory development in design work, and (3) to more broadly integrate the insights of different technical theories. 1.

. The Tutoring Research Group at the University of Memphis is developing an intelligent tutoring system which takes advantages of recent technological advances in the areas of semantic processing of natural language, world knowledge representation, multimedia interfaces, and fuzzy descriptions. The tutoring interaction is based on in-depth studies of human tutors, both skilled and unskilled. Latent semantic analysis will be used to semantically process and provide a representation for the student's contributions. Fuzzy production rules select appropriate topics and tutor dialogue moves from a rich curriculum script. The production rules will implement a variety of different tutoring styles, from a basic untrained tutor to one which uses sophisticated pedagogical strategies. The tutor will be evaluated on the naturalness of its interaction, with Turing-style tests, by comparing different tutoring styles, and by judging learning outcomes. 1 Introduction At the University of Memphis, our...

A knowledge digraph defines a set of semantic (or syntactic) associative relationships among propositions in a text (e.g., Graesser and Clark (1985) conceptual graph structures and the causal network analysis of Trabasso & van den Broek, 1985). This paper introduces the Knowledge Digraph Contribution (KDC) data analysis methodology for quantitatively measuring the degree to which a given knowledge digraph can account for the occurrence of specific sequences of propositions in recall, summarization, talkaloud, and question-answering protocol data. KDC data analysis provides statistical tests for selecting the knowledge digraph which "best-fits" a given data set. KDC data analysis also allows one to test hypotheses about the relative contributions of each member in a set of knowledge digraphs. The validity of specific knowledge digraph representational assumptions may be evaluated by comparing human protocol data with protocol data generated by sampling from the KDC distribution. Specifi...

Latent Semantic Analysis (LSA) has been used to represent the domain of computer literacy in AutoTutor, a fully automated computer tutor. The analyses in the present study support the claim that the 200-dimensional LSA space captures aspects of the structured mental models that underlie computer literacy. Knowledge structures were constructed that contained causal networks, goal/plan/action hierarchies, and taxonomic hierarchies. The proximity of a pair of nodes (i.e., concept, state, event, action, goal) in these structures predicted the cosine similarity scores that are routinely computed in LSA analyses.

Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000. Approved for public release; further dissemination unlimited. Issued by Sandia National Laboratories, operated for the United States Department of Energy by Sandia Corporation. NOTICE: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government, nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, make any warranty, express or implied, or assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represent that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement,

This report contains a review of available task analytic data and protocols pertinent to heavy vehicle operation and determination of the availability and relevance of such data to heavy vehicle driver workload assessment. Additionally, a preliminary consideration of development of safety-relevant criteria was pursued, and relevance of a review of the relationship between risk-taking behavior and workload was examined. Task analysis data included American, Canadian, and European sources which varied substantially in format and content, and were largely oriented to support training and certification. A variety of protocols including activity analysis, interviews and commentary, driving or protocol analysis, critical incident technique, subjective workload ratings, visual allocation measures, on-the-road driver-vehicle peformance monitoring, safety criticality ratings, and rankings were identified.No fully devloped methodologies or criteria were found by which to predict accident ra...

A growing number of applications seek to incorporate automatically generated narrative structure into interactive virtual environments. In this paper, we evaluate a representation for narrative structure generated by an automatic planning system by 1) mapping the plans that control plot into conceptual graphs used by QUEST, an existing framework for question-answering analysis that includes structures for modeling a reader's narrative comprehension and 2) using methods originally employed by QUEST's developers to determine if the plan structures can serve as effective models of the understanding that human users form after viewing corresponding stories played out within a virtual world. Results from our analysis are encouraging, though additional work is required to expand the plan language to cover a broader class of narrative structure.