Context Management of Conversational Agent using Two-Stage Bayesian Network

2단계 베이지안 네트워크를 이용한 대화형 에이전트의 문맥 관리

  • 홍진혁 (연세대학교 컴퓨터과학과) ;
  • 조성배 (연세대학교 컴퓨터산업공학부)
  • Published : 2004.02.01

Abstract

Conversational agent is a system that provides users with proper information and maintains the context of dialogue on the natural language. Analyzing and modeling process of user's query is essential to make it more realistic, for which Bayesian network is a promising technique. When experts design the network for a domain, the network is usually very complicated and is hard to be understood. The separation of variables in the domain reduces the size of networks and makes it easy to design the conversational agent. Composing Bayesian network as two stages, we aim to design conversational agent easily and analyze user's query in detail. Also, previous information of dialogue makes it possible to maintain the context of conversation. Actually implementing it for a guide of web pages, we can confirm the usefulness of the proposed architecture for conversational agent.

대화형 에이전트는 언어를 이용하여 사용자에게 적절한 정보를 제공하고 대화의 문맥을 유지하는 시스템이다. 대화형 에이전트를 더욱 현실적으로 만들기 위해서는 사용자 질의에 대한 분석과 모델링 과정이 필수적이며, 베이지안 네트워크가 이를 위한 대표적인 방법 중 하나이다. 보통 대상영역을 위한 네트워크는 매우 복잡하고 이해하기가 어렵기 때문에 네트워크를 구성하는 변수들을 분리함으로써 대화형 에이전트를 보다 쉽게 설계할 수 있다. 본 논문에서는 대화형 에이전트의 질의 분석모듈을 2단계 베이지안 네트워크로 구성하여, 설계를 보다 용이하게 하였고 문형을 고려한 세부적인 질의분석을 가능하도록 하였다. 웹 페이지를 소개하는 에이전트에 적용하여 제안한 대화형 에이전트 구조의 유용성을 보였다.

Keywords

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