David Leake

This book presents a selection of recent progress, issues, and directions for the future of case-based reasoning. It includes chapters addressing fundamental issues and approaches in indexing and retrieval, situation assessment and similarity assessment, and in case adaptation. Those chapters provide a" case-based" view of key problems and solutions in context of the tasks for which they were developed. It also presents lessons learned about how to design CBR systems and how to apply them to real-world problems. The final chapters include a perspective on the state of the field and the most important directions for future impact. The case studies presented involve a broad sampling of tasks, such as design, education, legal reasoning, planning, decision support, problem-solving, and knowledge navigation. In addition, they experimentally examine one of the fundamental tenets of CBR, that reasoning from prior …

Case-based reasoning (CBR) is an approach to problem solving that emphasizes the role of prior experience during future problem solving (i.e., new problems are solved by reusing and if necessary adapting the solutions to similar problems that were solved in the past). It has enjoyed considerable success in a wide variety of problem solving tasks and domains. Following a brief overview of the traditional problem-solving cycle in CBR, we examine the cognitive science foundations of CBR and its relationship to analogical reasoning. We then review a representative selection of CBR research in the past few decades on aspects of retrieval, reuse, revision and retention.

A father taking his two-year-old son on a walk reaches an intersection and asks where they should turn. The child picks a direction, the direction they turned in at that intersection the day before to go to the supermarket. The child explains:\I have a memory: Buy donut."

Explanation-based learning (EBL) is a very powerful method for category formation. Since EBL algorithms depend on having good explanations, it is crucial to have effective ways to build explanations, especially in complex real-world situations where complete causal information is not available.When people encounter new situations, they often explain them by remembering old explanations, and adapting them to fit. We believe that this case-based approach to explanation holds promise for use in AI systems, both for routine explanation and to creatively explain situations quite unlike what the system has encountered before.Building new explanations from old ones relies on having explanations available in memory. We describe explanation patterns (XPs), knowledge structures that package the reasoning underlying explanations. Using the SWALE system as a base, we discuss the retrieval and modification …

Case-based reasoning means reasoning based on previous cases or experiences. A case-based reasoner uses remembered cases to suggest a means of solving a new problem, to suggest how to adapt a solution that doesn't quite work, to warn of possible failures, to interpret a new situation, to critique a solution in progress, or to focus attention on some part of a situation or problem. An example will illustrate.A host is planning a meal for a set of people who include, among others, several people who eat no meat or poultry, one of whom is also allergic to milk products, several meat-and-potatoes men, and her friend Anne. Since it is tomato season, she wants to use tomatoes as a major ingredient in the meal. As she is planning the meal, she remembers:

Experience with the growing number of large-scale CBR systems has led to increasing recognition of the importance of case-base maintenance. Multiple researchers have addressed pieces of the case-base maintenance problem, considering such issues as maintaining consistency and controlling case-base growth. However, despite the existence of these cases of case-base maintenance, there is no general framework of dimensions for describing case-base maintenance systems. Such a framework would be useful both to understand the state of the art in case-base maintenance and to suggest new avenues of exploration by identifying points along the dimensions that have not yet been studied. This paper presents a first attempt at identifying the dimensions of case-base maintenance. It shows that characterizations along such dimensions can suggest avenues for future case-base maintenance research …

7.1 Overview of Nonmotivational Anomalies 153 7.2 PLAN-EXECUTION-FAILURE 154 7.3 BLOCK A GE-VIOLA TI ON 160 7.4 PROCESS-EXECUTION-FAIL URE 162 7.5 DEVICE-FAIL URE 164 7.6 INFORMA TI ON-FAIL URE 165 7.7 UNUSUAL-FEATURE 166 7.8 EE AT URE-D UR A TION-FAIL URE 167 7.9 Judging the Vocabulary 168 7.10 Conclusion 171

In current CBR systems, case adaptation is usually performed by rule-based methods that use task-specific rules hand-coded by the system developer. The ability to define those rules depends on knowledge of the task and domain that may not be available a priori, presenting a serious impediment to endowing CBR systems with the needed adaptation knowledge. This paper describes ongoing research on a method to address this problem by acquiring adaptation knowledge from experience. The method uses reasoning from scratch, based on introspective reasoning about the requirements for successful adaptation, to build up a library of adaptation cases that are stored for future reuse. We describe the tenets of the approach and the types of knowledge it requires. We sketch initial computer implementation, lessons learned, and open questions for further study.

Effective knowledge management maintains the knowledge assets of an organization by identifying and capturing useful information in a usable form, and by supporting refinement and reuse of that information in service of the organization’s goals. A particularly important asset is the" internal" knowledge embodied in the experiences of task experts that may be lost with shifts in projects and personnel. Concept Mapping provides a framework for making this internal knowledge explicit in a visual form that can easily be examined and shared. However, it does not address how relevant concept maps can be retrieved or adapted to new problems. CBR is playing an increasing role in knowledge retrieval mad reuse for corporate memories, and its capabilities are appealing to augment he concept mapping process. This paper describes ongoing research on a combined CBI~/CMap framework for managing aerospace design knowledge. Its approach emphasizes interactive capture, access, and application of knowledge representing different experts’ perspectives, and unobtrusive learning as knowledge is reused.

Experience with the growing number of large‐scale and long‐term case‐based reasoning (CBR) applications has led to increasing recognition of the importance of maintaining existing CBR systems. Recent research has focused on case‐base maintenance (CBM), addressing such issues as maintaining consistency, preserving competence, and controlling case‐base growth. A set of dimensions for case‐base maintenance, proposed by Leake and Wilson, provides a framework for understanding and expanding CBM research. However, it also has been recognized that other knowledge containers can be equally important maintenance targets. Multiple researchers have addressed pieces of this more general maintenance problem, considering such issues as how to refine similarity criteria and adaptation knowledge. As with case‐base maintenance, a framework of dimensions for characterizing more general …

An important focus of recent CBR research is on how to develop strategies for achieving compact, competent case-bases, as a way to improve the performance of CBR systems. However, compactness and competence are not always good predictors of performance, especially when problem distributions are non-uniform. Consequently, this paper argues for developing methods that tie case-base maintenance more directly to performance concerns. The paper begins by examining the relationship between competence and performance, discussing the goals and constraints that should guide addition and deletion of cases. It next illustrates the importance of augmenting competence-based criteria with quantitative performance-based considerations, and proposes a strategy for closely re.ecting adaptation performance e.ects when compressing a case-base. It then presents empirical studies examining the …

This book constitutes the refereed proceedings of the Second International Conference on Case-Based Reasoning, ICCBR-97, held in Providence, RI, USA, in July 1997. The volume presents 39 revised full scientific papers selected from a total of 102 submissions; also included are 20 revised application papers. Among the topics covered are representation and formalization, indexing and retrieval, adaptation, learning, integrated approaches, creative reasoning, CBR and uncertainty. This collection of papers is a comprehensive documentation of the state of the art in CBR research and development.

Brings together a diversity of research on goal-driven learning to establish a broad, interdisciplinary framework that describes the goal-driven learning process. In cognitive science, artificial intelligence, psychology, and education, a growing body of research supports the view that the learning process is strongly influenced by the learner's goals. The fundamental tenet of goal-driven learning is that learning is largely an active and strategic process in which the learner, human or machine, attempts to identify and satisfy its information needs in the context of its tasks and goals, its prior knowledge, its capabilities, and environmental opportunities for learning. This book brings together a diversity of research on goal-driven learning to establish a broad, interdisciplinary framework that describes the goal-driven learning process. It collects and solidifies existing results on this important issue in machine and human learning and presents a theoretical framework for future investigations. The book opens with an an overview of goal-driven learning research and computational and cognitive models of the goal-driven learning process. This introduction is followed by a collection of fourteen recent research articles addressing fundamental issues of the field, including psychological and functional arguments for modeling learning as a deliberative, planful process; experimental evaluation of the benefits of utility-based analysis to guide decisions about what to learn; case studies of computational models in which learning is driven by reasoning about learning goals; psychological evidence for human goal-driven learning; and the ramifications of goal-driven …

The ability of case-based reasoning (CBR) systems to apply cases to novel situations depends on their case adaptation knowledge. However, endowing CBR systems with adequate adaptation knowledge has proven to be a very difficult task. This paper describes a hybrid method for performing case adaptation, using a combination of rule-based and case-based reasoning. It shows how this approach provides a framework for acquiring flexible adaptation knowledge from experiences with autonomous adaptation and suggests its potential as a basis for acquisition of adaptation knowledge from interactive user guidance. It also presents initial experimental results examining the benefits of the approach and comparing the relative contributions of case learning and adaptation learning to reasoning performance.

Introspective reasoning about a system's own reasoning processes can form the basis for learning to refine those reasoning processes. The ROBBIE1 system uses introspective reasoning to monitor the retrieval process of a case-based planner to detect retrieval of inappropriate cases. When retrieval problems are detected, the source of the problems is explained and the explanations are used to determine new indices to use during future case retrieval. The goal of ROBBIE's learning is to increase its ability to focus retrieval on relevant cases, with the aim of simultaneously decreasing the number of candidates to consider and increasing the likelihood that the system will be able to successfully adapt the retrieved cases to fit the current situation. We evaluate the benefits of the approach in light of empirical results examining the effects of index learning in the ROBBIE system.