Andreas C. Lemke

The role of critiquing in cooperative problem solving

Cooperative problem-solving systems help users design solutions themselves as opposed to having solutions designed for them, Critiquing—presenting a reasoned opinion about a user’s product or action–is a major activity of a cooperative problem-solving system. Critics make the constructed artifact “talk back” to the user. Conditions under which critics are more appropriate than autonomous expert systems are discussed. Critics should be embedded in integrated design environments along with other components, such as an argumentative hypertext system, a specification component, and a catalog. Critics support learning as a by-product of problem solving. The major subprocesses of critiquing are goal acquisition, product analysis, critiquing strategies, adaptation capability, explanation and argumentation, and advisory capability. The generality of the critiquing approach is demonstrated by discussing critiquing systems developed in our group and elsewhere. Limitations of many current critics include their inability to learn about specific user goals and their intervention strategies.

Knowledge-based help systems

Our research goals are to understand the nature of, construct and evaluate intelligent interfaces as knowledge-based systems. In this paper we demonstrate the need for help systems as an essential part of human-computer communication. Help strategies are based on a model of the task (to understand what the user is doing or which goals he/she1 wants to achieve) and a model of the user (to guarantee that these systems are non-intrusive and that they pay attention to the needs of individual users). We illustrate that passive and active help systems have to be constructed as knowledge-based systems. Two operational systems (PASSIVIST and ACTIVIST) are described to show the usefulness of this approach.

Construction kits and design environments: steps toward human problem-domain communication

Our goal is to build cooperative computer systems to augment human intelligence. In these systems, the communication between the user and the computer plays a crucial role. To provide the user with the appropriate level of control and a better understanding, we have to replace human-computer communication with human problem-domain communication, which allows users to concentrate on the problems of their domain and to ignore the fact that they are using a computer tool. Construction kits and design environments are tools that represent steps toward human problem-domain communication. A construction kit is a set of building blocks that models a problem domain. The building blocks define a design space (the set of all possible designs that can be created by combining these blocks). Design environments go beyond construction kits in that they bring to bear general knowledge about design (e.g., which meaningful artifacts can be constructed, how and which blocks can be combined with each other) that is useful for the designer. Prototypical examples of these systems (especially in the area of user interface design) are described in detail, and the feasibility of this approach is evaluated.

Supporting indirect collaborative design with integrated knowledge-based design environments

We are developing a conceptual framework and a demonstration system for collaboration among members of design teams when direct communication among these members is impossible or impractical. Our research focuses on the long-term, indirect communication needs of project teams rather than the short-term needs of face-to-face communication or electronic mail. We address these needs with integrated, domain-oriented design environments. Our conceptual framework and our system-building efforts address two major issues: (a) How does individual work blend into project work (especially in large projects that span great distances and time)? and (b) What role do the work objects play in this coordination? We use a specific domain-oriented design environment (NETWORK-HYDRA-for the design of computer networks) to illustrate our approach, and we discuss HYDRA as the underlying domain-independent, multifaceted architecture for design environments.

Using critics to empower users

We describe the critiquing approach to building knowledge-based interactive systems. Critiquing supports computer users in their problem solving and learning activities. The challenges for the next generation of knowledge-based systems provide a context for the development of this paradigm. We discuss critics from the perspective of overcoming the problems of high-functionality computer systems, of providing a new class of systems to support learning, of extending applications-oriented construction kits to design environments, and of providing an alternative to traditional autonomous expert systems. One of the critiquing systems we have built — JANUS, a critic for architectural design — is used as an example of the key aspects of the critiquing process. We also survey additional critiquing systems developed in our and other research groups.

Critics: an emerging approach to knowledge-based human-computer interaction

We describe the critiquing approach to building knowledge-based interactive systems. Critiquing supports computer users in their problem solving and learning activities. The challenges for the next generation of knowledge-based systems provide a context for the development of this paradigm. We discuss critics from the perspective of overcoming the problems of high-functionality computer systems, of providing a new class of systems to support learning, of extending applications-oriented construction kits to design environments, and of providing an alternative to traditional autonomous expert systems. One of the critiquing systems we have built—JANUS, a critic for architectural design—is used as an example for presenting the key aspects of the critiquing process. We then survey additional critiquing systems developed in our and other research groups. The paper concludes with a discussion of experiences and extensions to the paradigm.

Active help systems

Good on-line help systems are of crucial importance for the computer systems of the future. An increased functionality (required by the many different tasks which a user wants to do) will lead to an increased complexity. Empirical investigations have shown that on the average only 40% of the functionality of complex computer systems are used. Passive help systems (which require that the user requests help explicitly from the system) are of little use if the user does not know the existence of a system feature. Active help systems should guide and advise an user similar to a knowledgeable colleague or assistant.

Construction Kits and Design Environments: Steps Toward Human Problem-Domain Communication

Our goal is to build cooperative computer systems to augment human intelligence. In these systems the communication between the user and the computer plays a crucial role. To provide the user with the appropriate level of control and a better understanding, we have to replace human-computer communication with human problem-domain communication, which allows users to concentrate on the problems of their domain and to ignore the fact that they are using a computer tool.Construction kits and design environments are tools that represent steps towards human problem-domain communication. A construction kit is a set of building blocks that models a problem domain. The building blocks define a design space (the set of all possible designs that can be created by combining these blocks). Design environments go beyond construction kits in that they bring to bear general knowledge about design (e.g., which meaningful artifacts can be constructed, how and which blocks can be combined with each other that is useful for the designer. Prototypical examples of these systems (especially in the area of user interface design) are described in detail and the feasibility of this approach is evaluated.

Using cognitive simulation to develop user interface design principles

The authors develop theory-based user interface design principles. The goal is independent detailed simulations of user command production in the Unix operating system and Framer, a user-interface design tool. The simulations are based on the construction-integration theory and build on the action planning model developed by S.M. Mannes and W. Kintsch (1988). Use of the model provides insight into why certain types of command productions pose problems for Unix users and shows promise for explaining problems for user of Framer.<<ETX>>