<?xml version="1.0" standalone="yes"?>
<Paper uid="C92-2110">
  <Title>Design Tool Combining Keyword Analyzer and Case-based Parser for Developing Natural Language Database Interfaces</Title>
  <Section position="2" start_page="0" end_page="0" type="intro">
    <SectionTitle>
1 Introduction
</SectionTitle>
    <Paragraph position="0"> As the number of commercial on-line databases increases, so does user need for pragmatic natural language (NL) interface for communicating with tbose databases. Case-based parsing is an effective approach to constructing NL interfaces to databases \[1\] \[5\] \[7\] \[11\]. A standard case-based parser consists basically of a pattern marcher and a case base which stores a large number of linguistic pa~tern-concept pairs. In response to a new input query, the pattern matcher searches the case base for any matching linguistic patterns. If one is found, its concept portion is output as a semantic representation of the given input query. Though case-based parsing makes it easy to construct domain dependent NL interfaces, it has several serious drawbacks: * The application designer who uses it must define all possible linguistic patterns.</Paragraph>
    <Paragraph position="1"> * The application designer must also define a concept portion to correspond to each defined linguistic pattern.</Paragraph>
    <Paragraph position="2"> * Since such pattern-concept definitions will be highly dependent oo tile nature of the specific application, they must bc newly defined for each target system.</Paragraph>
    <Paragraph position="3"> In this paper, we propose a novel NL interface model, CAPIT (Cooperative Analyzer and Parser as Interface &amp;quot;Fool). It is a self-contained NL interface building tool for relational-like databases, and it integrates NL processing mechanisms with the mechanism used for the incremental acquisition of knowledge needed in that NL processing. CAPIT combines a simple keyword analyzer, KBP(Keyword-Based Parsing module), with a case-based parser, CBP(Case-Based Parsing module). KBP extracts only keywords from an input sentence, and constructs a meaning for the sentence from them. Since NL queries to on-line databases tend to be simple and straightforward, KIqP can interpret a majority of those queries. However, because it constructs the meaning only from the keywords, KBP sometimes fails to interpret them.</Paragraph>
    <Paragraph position="4"> The ease-based parser (CBP) is a supplemental module to KBP. CBP is a conventional case-based parser. It consists of a pattern matcher and a case base. Linguistic pattern-concept pairs are stored in the case base. CBP must process only those queries which KBP fails to interpret correctly. Since an application designer do not have to define all the possible linguistic patterns, his/her labor required to define linguistic pattern-concept pairs is less than that for a tool which employs a conventional case-based parser alone.</Paragraph>
    <Paragraph position="5">  We analyzed KBP's interpretation failures, and categorized the types of KBP's interpretation failures. We regard defining pattern-concept pairs for CBP as repairs of KBP's interpretation failures. We defined four repair types which are corresponding to KBP's typical interpretation failures. When all application designer encounters KBP's interpretation failure, he/she analyzes it, then selects the best and easiest repair type. Such a repair task is accomplished interactively between the application designer and the Pattern Definition Interviewer module (PDI).</Paragraph>
  </Section>
class="xml-element"></Paper>