Shallow Parsing of Spoken Estonian Using Constraint Grammar

In this paper we describe how we have adapted the syntactic analyzer of written Estonian to the spoken language. The Constraint Grammar shallow syntactic parser (Müürisep et al. 2003) was used for the automatic syntactic analysis of the corpus of Estonian spoken language (Hennoste et al. 2000). To adapt the parser, the clause boundary detection rules as well as some syntactic constraints had to be changed. Two new syntactic tags were also introduced. In the paper the introduced changes are described and the achieved results are analyzed. The parser determined the syntactic label unambiguosly for 90% of the words in the text in average, using the manually morphologically disambiguated text as an input. The error rate was less than 3%.