Qualitative simulation predicts the set of possible behaviors...

Abstract not found

In contrast to expectation-based, predictive views of discourse comprehension, a model is developed in which the initial processing is strictly bottom-up. Word meanings are activated, propositions are formed, and inferences and elaborations are produced without regard to the discourse context. However, a network of interrelated items is created in this manner, which can be integrated into a coherent structure through a spreading activation process. Data concerning the time course of word identification in a discourse context are examined. A simulation of arithmetic word-problem under-standing provides a plausible account for some well-known phenomena in this area. Discourse comprehension, from the viewpoint of a computa-tional theory, involves constructing a representation of a dis-course upon which various computations can be performed, the outcomes of which are commonly taken as evidence for com-prehension. Thus, after comprehending a text, one might rea-sonably expect to be able to answer questions about it, recall or summarize it, verify statements about it, paraphrase it, and SO on.

This chapter surveys the field of user modeling in artificial intelligence dialog systems. First, reasons why user modeling has become so important in the last few years are pointed out, and definitions are proposed for the terms 'user model ' and 'user modeling component'. Research within and outside of artificial intelligence which is related to user modeling in dialog systems is discussed. In Section 2, techniques for constructing user models in the course of a dialog are presented and, in Section 3, recent proposals for representing a wide range of assumptions about a user's beliefs and goals in a system's knowledge base are surveyed. Examples for the application of user models in systems developed to date are then given, and some social implications discussed. Finally, unsolved problems like coping with collective beliefs or resource-limited processes are investigated, and prospects for applicationoriented research are outlined. Although the survey is restricted to user models in naturallanguage dialog systems, most of the concepts and methods discussed can be extended to AI dialog systems in general.

An exploratory study was conducted of elementary school children searching a full-text electronic encyclo-pedia on CD-ROM. Twenty-eight third and fourth graders and 24 sixth graders conducted two assigned searches, one open-ended, the other one closed, after two demon-stration sessions. Keystrokes captured by the com-puter and observer notes were used to examine user information-seeking strategies from a mental model perspective. Older searchers were more successful in finding required information, and took less time than younger searchers. No differences in total number of moves were found. Analysis of search patterns showed that novices used a heuristic, highly interactive search strategy. Searchers used sentence and phrase queries, indicating unique mental models for this search sys-tem. Most searchers accepted system defaults and used the AND connective in formulating queries. Transi-tion matrix analyses showed that younger searchers generally favored query refining moves and older searchers favored examining title and text moves. Sug-gestions for system designers were made and future re-search questions were identified.

Over the past ten years, the use of sociological methods and sociological reasoning have become more prominent in the analysis and design of interactive systems. For a variety of reasons, one form of sociological enquiry, ethnomethodology, has become something of a favoured approach. Our goal in this paper is to investigate the consequences of approaching system design from the ethnomethodological perspective. In particular, we are concerned with how ethnomethodology can take a foundational place in the very notion of system design, rather than simply being employed as a resource in aspects of the process such as requirements elicitation and specification. We begin by outlining the basic elements of ethnomethodology, and discussing the place that it has come to occupy in CSCW and, increasingly, in HCI. We discuss current approaches to the use of ethnomethodology in systems design, and point to the contrast between the use of ethnomethodology for critique and for design. Currently, und...

13.44> . Drew Kessler for help with the SVE toolkit . The Virtual Environments group at Georgia Tech . The numerous experimental subjects who volunteered their time . Dawn Bowman iv TABLE OF CONTENTS Introduction ..................................................................... ................. 1 1.1 Motivation ..................................................................... ...............1 1.2 Definitions.......................................................... ..........................4 1.3 Problem Statement............................................................ ...............6 1.4 Scope of the Research............................................................. ..........7 1.5 Hypotheses........................................................... ........................8 1.6 Contributions........................................................ .....

One of the original motivations for qualitative physics research was the creation of a computational account of mental models. For instance, a key intuition often associated with mental models is that they are runnable, i.e., there is a sense of deriving answers via mental simulation rather than logical reasoning. This paper examines three explanations for runnability, and argues that none of them is sufficient. Instead, a hybrid model combining aspects of all three is proposed, focusing on the integration of ideas from qualitative physics with ideas from analogical processing. Some psychological implications of this hybrid model are discussed.

Four experiments explored participants' understanding of the abstract principles goincipl coinci simulatios o coulat adaptive systems. Experiments 1, 2, and 3shoBU better transfero abstract principlesacroc simulatioA that were relatively dissimilar, and that this e#ect was dueto participantswho perfocip relativelypolat o the initialsimulatioB In Experiment 4, participantsshoic better abstract understandingo asimulatio when it was depicted withcohA@CU rather than idealized graphical elements.Homents fo pom perfos.Aq/ the idealizedversio o the simulatio transferred betterto a newsimulatio gomulat by the same abstractioU The results are interpreted in termso cosAq6BP--A between abstract and codAP)U coAP)U@/A o thesimulatio)/ Individualsproi toiv coivid coividual tendto oodAPU abstractioH whenconA)C@ pro)C@qUA o superficial similarities are salient.

A contemporary approach to describing and theorizing about joint human endeavor is to posit “knowledge in common ” as a basis for awareness and coordination. Recent analysis has identified weaknesses in this approach even as it is typically employed in relatively simple task contexts. We suggest that in realistically complex circumstances, people share activities and not merely concepts. We describe a framework for understanding joint endeavor in terms of four facets of activity awareness: common ground, communities of practice, social capital, and human development. We illustrate the sort of analysis we favor with a scenario from emergency management, and consider implications and future directions for system design and empirical methods. 1.