As Soloway attracted over 400 pnrticipants from all of Pittsburgh, Pittsburgh, Penn., described the changes in what he felt over the world who gathered to present 8-10 May 1987. The conference the construction of mechanisms and concerning AI and education This article cochairmen, Stellan Ohlsson and explanations last year to the design of presents a synopsis of the major Jeff Bonar, also gave brief welcomes to artifacts today, he was clearly giving presentations and an overview the participants. With so about transference, leading Soloway many attendees from abroad (The to conclude that transference is not Netherlands, Japan, Canada, West the ultimate goal for teaching and Germany, England, Sweden, France, tutoring programming. Instead, the and Hong Kong were all represented concern should be for the development by speakers), the international flavor of synthesis skills and "highorder of the conference was well established. The obvious disappointment This model does not vary significantly of the audience could be from standard software engineering felt. However, instead of giving the opening address, "Programming requiring these steps be followed in a as Artifact Design." This change strict order, Soloway contends that worked out well because Soloway the way real programmers work best acted like a cheerleader, getting the is to bounce from one stage to another crowd fired up about the subject of AI as the need arises. WINTER 1987 97 Andy di Sessa, in his talk "Social much rigidity has recently been the differences between beginner and Niches for Future Software," focused imposed on programmers by the engi-expert. Finally, Wender suggested that on the need to provide a medium neering approach. He demonstrated him, one could easily mistake him for teacher. Some of the kinds of software he felt should ... He considers current applications to be "the He also suggested that "current programming is to synthesis as a hammer is to a thumb. Each is as likely to challenge to the computer science der was echoed by Ben du Boulay in cause pain as [it is] to get the job community to develop higher-level "What Should a Programming Environment done." The Like?" Bonar's comment in his opening Beyond the usual categories supplied emphasis should be on synthesis welcome that we are "on the verge by the conference structure, several skills for designing, generating, and of a breakthrough" in developing themes linked many of the papers evaluating alternative artifacts that tutoring systems concerned du and presentations.

In the restaurant script, notated as $RESTAURANT, the roles might directly to the United Press International Yale researchers explored intentionality include customer, waitress, and cook; news wire and could skim news One of the earliest programs to the props could be a menu, table, and stories in dozens of different domains, embody goals and plans within the silverware; the locations could be the and produce summaries in several languages. CD paradigm was Jim Meehan's bar, dining area, and kitchen; and the On the DEC-20 (which by TALESPIN, which made up stories events would include arriving, seating, 1978 had replaced the PDP-101, similar to the fables of Aesop.

A number of tools that support the development, execution, and maintenance of knowledge-based systems are marketed commercially. Many of these tools, however, are designed for applications that can be executed on personal computers and are not suitable for building large knowledge-based systems. The market for knowledge engineering tools designed for applications that require the computational power of a Lisp machine or an engineering workstation is dominated by a few vendors. This article is an assessment of the current state of tools used to build large knowledge-based systems. This assessment is based on the collective strengths and weaknesses of several tools that have been evaluated. In addition, an estimate is made of the features that will be required in the next generation of tools.

We offer a simple mechanism, that of metalingual definition (D. G. Hays, The Meaning of a Term is a Function of the Theory in Which It Occurs, SIGLASH Newsletter, 1973, 6, 4:S-11).

This report contains a historical perspective on previous Distributed Artificial Intelligence Workshops, highlights of the roundtable discussions, and a collection of research abstracts submitted by the participants.

The (CSCW '86) was held in Austin, participants). The three-day report introduces the field of computersupported Texas, on 3-5 December 1986. It was event included nine paper sessions: cooperative work, describes the sponsored by the Microelectronics supporting face-to-face groups, empirical CSCW '86 program, and discusses the significance and Computer Technology Corporation studies, supporting distributed of the conference results An (MCC) Software Technology Program groups, hypertext systems, underlying introduction to the follow-on conference, in cooperation with the Association technology for collaborative systems, CSCW '88, is also provided for Computing Machinery (ACM) collaboration research, multimedia and its special interest groups on software and multiuser interfaces, industrial engineering (SIGSOFT), human experiences with CSCW, and coordination computer interaction (SIGCHI), and and decision making. There office information systems (SIGOIS); were also four panel sessions; the topics the Institute for Electrical and Electronic were collaboration and offices, collaborative Engineers (IEEE) Computer design studies, from theories Society; the American Association for to systems, and trends and markets Artificial Intelligence (AAAI); The for computer-supported group Information Management Society work. As the invited dinner speaker, (TIMS); and the Software Psychology Robert Howard, noted author on the Society.

This article presents an approach to a graduate-level course in expert, knowledge-based, problem-solving systems. The core of the course, and this article, is a set of questions called a profile, that can be used to characterize and compare each system studied.

This article examines the direction in which knowledge bases are constructed for diagnosis and decision making. When building an expert system, it is traditional to elicit knowledge from an expert in the direction in which the knowledge is to be applied, namely, from observable evidence toward unobservable hypotheses. However, experts usually find it simpler to reason in the opposite direction-from hypotheses to unobservable evidence-because this direction reflects causal relationships. Therefore, we argue that a knowledge base be constructed following the expert's natural reasoning direction, and then reverse the direction for use. This choice of representation direction facilitates knowledge acquisition in deterministic domains and is essential when a problem involves uncertainty. We illustrate this concept with influence diagrams, a methodology for graphically representing a joint probability distribution. Influence diagrams provide a practical means by which an expert can characterize the qualitative and quantitative relationships among evidence and hypotheses in the apporiate direction. Once constructed, the relationships can easily be reserved into the less intuitive direction in order to perform inference inference and diagnosis. In this way, knowledge acquisition is made cognitively simple; the machine carries the burden of translating the representation.

The questions of how humans process uncertain information is important to the development of knowledge-based systems in term of both knowledge acquisition and knowledge representation. This article reviews three bodies of psychological research that address this question: human perception, human probabilistic and statistical judgement, and human choice behavior. The general conclusion is that human behavior under certainty is often suboptimal and sometimes even fallacious. Suggestions for knowledge engineers in detecting and obviating such errors are discussed. The requirements for a system designed to reduce the effects of human factors in the processing of uncertain knowledge are introduced.

The First International Workshop on User Modeling in Natural Language Dialogue Systems was held 30-31 August 1986 in Maria Laach, West Germany. Issues addressed by the participants included the appropriate contents of a user model, techniques for constructing user models in both understanding and generating natural language dialogue, and the development of general user-modeling systems. This article includes an overview of the presentations made at the workshop. It is a compilation of the author's impressions and observations and is, therefore, undoubtedly incomplete; and at times might fail to accurately represent the views of the researcher presenting the work.