Abductive speech act recognition, corporate agents and the COSMA system

This chapter presents an overview of the DISCO project\u27s solutions to several problems in natural language pragmatics. Its central focus is on relating utterances to intentions through speech act recognition. Subproblems include the incorporation of linguistic cues into the speech act recognition process, precise and efficient multiagent belief attribution models (Corporate Agents), and speech act representation and processing using Corporate Agents. These ideas are being tested within the COSMA appointment scheduling system, one application of the DISCO natural language interface. Abductive speech act processing in this environment is not far from realizing its potential for fully bidirectional implementation

Corporate agents

The logic of belief and intention in situations with multiple agents is increasingly well understood, but current formal approaches appear to face problems in applications where the number of agents greatly exceeds two. We provide an informal development of Corporate Agents, an intensional approximation of individual and group states which treats groups symmetrically with autonomous agents. Corporate Charters, constraints derived from typical patterns of information flow, replace detailed reasoning about the propagation of attitudes in most contexts. The approximation to an ideal logical formulation is not tight, but the model appears to function well in information-poor environments and fails in ways related to characteristic human errors. It may therefore be particularly appropriate to application in the area of natural language discourse

COSMA - multi-participant NL interaction for appointment scheduling

We discuss the use of NL systems in the domain of appointment scheduling. Appointment scheduling is a problem faced daily by many people and organizations, and typically solved using communication in natural language. In general, cooperative interaction between several participants is required whose calendar data are distributed rather than centralized. In this distributed multi-agent environment, the use of NL systems makes it possible for machines and humans to cooperate in solving scheduling problems. We describe the COSMA (Cooperative Schedule Managament Agent) system, a secretarial assistant for appointment scheduling. A central part of COSMA is the reusable NL core system DISCO, which serves, in this application, as an NL interface between an appointment planning system and the human user. COSMA is fully implemented in Common Lisp and runs on Unix Workstations. Our experience with COSMA shows that it is a plausible and useful application for NL systems. However, the appointment planner was not designed for NL communication and thus makes strong assumptions about sequencing of domain actions and about the error-freeness of the communication. We suggest that further improvements of the overall COSMA functionality, especially with regard to flexibility and robustness, be based on a modified architecture

Online Educational Outcomes Could Exceed Those of the Traditional Classroom

An axiom of online education is that teachers should not mechanically translate existing courses into an online format. If so, how should new or ongoing courses be reshaped for the online environment and why? The answers come both from the opportunities offered by the structure of online education and from a body of research from cognitive psychology and cognitive science that provides insight into the way people actually learn. Freed from the time and space constraints inherent in face-to-face higher education settings as well as the deeply ingrained expectations of both teachers and students, online education provides a more flexible palette upon which evidence-based ideas about learning can be integrated into course structure and design. As a result, online education can potentially deliver learning experiences and outcomes that are superior to typical face-to-face classrooms. The ability to integrate experiences that stimulate real, long lasting learning represents one of online education’s greatest potential benefits

Net: A Utility for Building Regular Process Networks on the BBN Butterfly Parallel Processor

Coarse-grained parallel architectures like the BBN Butterfly are difficult to use without tools for building networks of communicating processes. Net is a tool for creating a useful class of process networks. This report describes the Net utility, an example application, and some design decisions and experiences

Thesis Proposal: A Plan-Based Approach to Conversational Implicature

Thesis Proposal.Implicatures are those propositions that must be inferred from an utterance in order to make sense of it in context, but which are not truth conditions or entailments of that utterance. Conversational implicatures are those that can be explained by general principles rather than lexical choice. Conversational implicature was defined in philosophy and discussed in linguistics, but lacks an adequate account in any discipline. For the computational linguist, this means that much information conveyed indirectly in discourse has no computational model. We show that knowledge of goals and plans is necessary for the computation of some implicatures, and very useful for a much larger class of implicatures. Our model uses a set of inference rules about STRIPS-style plans for implicature computation. It incorporates a computational model of speech acts (based on propositional attitudes) and surface speech acts (based on linguistic features). We propose an implementation, and relate it to other research in computational linguistics

Two Constraints on Speech Act Ambiguity

Existing plan-based theories of speech act interpretation do not account for the conventional aspect of speech acts. We use patterns of linguistic features (e.g. mood, verb form, sentence adverbials, thematic roles) to suggest a range of speech act interpretations for the utterance. These are filtered using plan-based conversational implicatures to eliminate inappropriate ones. Extended plan reasoning is available but not neces.'y for familiar forms. Taking speech act ambiguity seriously, with these two constraints, explains how "Can you pass the salt?" is a ical indirect request while "Are you typ . able to pass the salt?" m not