Abstract: Ripple down rules have addressed two of the major limitations of first generation Expert Systems (ES), the maintenance and knowledge acquisition (KA) bottleneck problems. This is achieved through acquiring knowledge directly from an expert, the use of an exception structure for knowledge representation and the storing of the cornerstone case associated with each rule. Just as RDR has offered a paradigm shift in the way these problems were solved, it is expected that RDR can offer a new approach to the issue of knowledge reuse. Due the poor acceptance of ES by end-users, our focus is more on reusing knowledge in different modes, such as explanation, critiquing or ‘what-if ’ within the same domain rather than the more conventional approach of reusing problem-solving methods or ontologies to solve a similar problem in a somewhat differerent domain. An evaluation of RDR for reuse showed that many modes of use were possible without any change to the knowledge or its structure but that some modes required understanding of the models represented. Since RDR does not require analysis or modeling of the domain for KA, maintenance or finding conclusions we have incorporated ideas from Formal Concept Analysis (FCA) to allow concepts and the relationships between them to be identified and explored. The addition of FCA tools to RDR is described in this paper. 1. The Reuse of Knowledge The reuse of knowledge should result in potential savings

Critiquing: Effective Decision Support in Time-Critical Domains Abigail S. Gertner Bonnie L. Webber (Supervisor) The TraumAID system is a tool for assisting physicians during the initial definitive management phase of patients with severe injuries. Originally, TraumAID was conceived as a rule-based expert system combined with a planner. After this architecture had been implemented and evaluated, we began to face the issue of how TraumAID could communicate its plans to physicians in order to influence their behavior and have a positive effect on patient outcome. It was hypothesized that a critiquing approach, in which the system is told what actions the user intends to carry out and produces a critique in response to those intentions, might be appropriate. To meet the needs of physicians engaged in managing trauma cases, critiques must be updated and made available rapidly. They must be clear and succinct, containing only relevant information while still including enough justification ...

Design critiquing systems are a type of intelligent user interface used to support human designers in decision making. This paper places design critics in the larger context of intelligent user interface approaches and surveys several critiquing systems. Each approach and system is evaluated with respect to a five-phase design improvement process. This paper concludes with a summary of the state of the art in critiquing systems and recommendations for future research directions. 1.

The work reported in this thesis is motivated by the belief that knowledge-based systems (KBS) research needs to focus more on users ’ needs and cater for the various decision situations in which users will find themselves. To build individual systems that cater for all the activities that may be needed is not feasible or desirable. The problems associated with capturing knowledge are well known and the ability to capture knowledge once and access and manipulate the knowledge in multiple ways is highly desirable. It adds value to the original knowledge and offers all the benefits associated with the reuse of resources. Thus, the problem becomes one of knowledge reuse. The research question pursued in this thesis is “can knowledge captured for one purpose, such as consultation, be reused to support a wide range of alternative purposes, such as critquing or tutoring, allowing the user to answer different types of questions according to their current circumstances”? Further, this question was to be answered in a situated cognition, dynamic knowledge framework. The system developed in this thesis is based on the Multiple Classification Ripple Down Rule (MCRDR) knowledge acquisition and representation technique. MCRDR is a form of casedbased

Software design is a cognitively challenging task. Most software design tools provide support for editing, viewing, storing, and transforming designs, but lack support for the essential and difficult cognitive tasks facing designers. These cognitive tasks include decision-making, decision ordering, and task-specific design understanding. This paper describes Argo/UML, an object-oriented design tool using the Unified Modeling Language design notation. Argo/UML supports several identified cognitive needs of software designers. This support is provided in the form of design tool features. We describe each feature in the context of Argo/UML and provide enough detail to enable other tool builders to provide similar support in their own tools. We also discuss our implementation of the UML and XMI standards, and our development approach. Keywords: UML, XMI, Cognitive support, Open-source software. 1.

In the past, little attention has been paid to critiquing in domains in which reasoning, planning and action are interleaved, or in which actions can change the agent's knowledge in ways that affect subsequent reasoning and planning. This paper discusses the demands these characteristics make on a critiquing system. The goal-directed approach to critiquing that I am developing interacts with a planner both to infer the user's goals and to determine the system's preferences. The model is able to detect interacting goals and comment when two goals may be addressed with a single action. It also detects when unpredictable outcomes may affect actions that have been planned for. The model is being implemented as an interface to TraumAID, a decision support system for the management of severe injuries. 1 Introduction Since its introduction a little more than ten years ago, the term critiquing has been used to describe a wide variety of systems. Basically, a critiquing system is anything that...

: The difficulties associated with acquirinng and validating knowledge have driven researchers to focus on ways to reduce this bottleneck in the development of knowledge based systems. Unfortunately, the needs of users have taken a back seat with the needs of knowledge engineers moving into the driver's seat. This paper suggests that reuse is a key issue for end-users but a different type of reuse to what is being currently pursued. A prototype system is described that allows knowledge to be owned and controlled by the user. Through the use of a knowledge acquisition and representation technique known as ripple-down rules (RDR) it is possible for the user to easily and rapidly capture, maintain and validate knowledge and perform inferencing. Additional activities such as critiquing, tutoring and 'what-if' analysis may also be supported by RDR through the inclusion of a set-theortical approach to data analysis known as Formal Concept Analysis (FCA). FCA allows an abstraction hierarchy o...

This paper argues that effectively communicating information to users who are involved in timecritical activities requires specialized capabilities for evaluating situations, filtering out the appropriate information, and producing easily accessible output. Simply displaying advice under such circumstances is unlikely to have a significant impact since it requires having the user's full attention on the system. An alternative is to reduce the amount of information presented by the system by adapting the output to the user's intended plan. This can be done by evaluating and critiquing the user's proposed actions in such a way that a critique is only given if there is a significant discrepancy between the user's intentions and the system's recommendations. This paper presents an approach to critiquing proposed actions during an ongoing process of planning and execution under critical time constraints. The problems addressed by this work include inferring the user's underlying intentions...

: Many KA research groups are currently focused on the reuse and sharing of ontologies as a means to alleviate the KA bottleneck. Such endeavours often take for granted that a shared view already exists and thereby avoid the problem of reconciling differences. A fundamental problem associated with reuse and sharing is that the underlying ontological and terminological assumptions have not been made sufficiently explicit or agreed upon. The approach suggested in this paper is to allow experts to develop their own knowledge base using a simple knowledge acquisition and representation technique known as Ripple Down Rules and then to apply our reconciliation process which relies on Formal Concept Analysis to build a shared knowledge base. A general framework for this approach is described together with an illustration using the SISYPHUS III knowledge acquisition material. 1. Sharing Knowledge -- the Holy Grail or a Pipe Dream ? Many knowledge acquisition (KA) research groups are currentl...

: The poor acceptance of ES technology by users has been attributed to the lack of attention to computer and user cooperation issues in knowledge based systems (KBS). While the traditional question-conclusion style of interaction may be appropriate in many circumstances, it is not necessarily the best or the only mode that users may require. Teaching, causal explanation/modeling, critiquing, `what-if' analysis and even knowledge acquisition are some of the possible modes of interaction. If we are able to adapt knowledge already captured to a wide range of modes we can add value to the knowledge resource. Ripple down rules have addressed two of the major limitations of first generation ES, the maintenance and knowledge acquisition (KA) bottleneck problems. This is achieved through acquiring knowledge directly from an expert, the use of an exception structure for knowledge representation and the storing of the cornerstone case associated with each rule. Just as RDR has offered a paradigm...