The effect of alternative tree representations on tree bank grammars

Details The effect of alternative tree representations on tree bank grammars The effect of alternative tree representations on tree bank grammars

1997-11-20

arxiv.org/abs/cmp-lg/9711011v2

Computer Science

Computation and Language

Adds missing bibliography (sorry!), 11 pages, to appear in Proceedings of NeMLAP 3, uses epic.sty and eepic.sty

Scientific paper

The performance of PCFGs estimated from tree banks is sensitive to the particular way in which linguistic constructions are represented as trees in the tree bank. This paper presents a theoretical analysis of the effect of different tree representations for PP attachment on PCFG models, and introduces a new methodology for empirically examining such effects using tree transformations. It shows that one transformation, which copies the label of a parent node onto the labels of its children, can improve the performance of a PCFG model in terms of labelled precision and recall on held out data from 73% (precision) and 69% (recall) to 80% and 79% respectively. It also points out that if only maximum likelihood parses are of interest then many productions can be ignored, since they are subsumed by combinations of other productions in the grammar. In the Penn II tree bank grammar, almost 9% of productions are subsumed in this way.

Affiliated with

Also associated with

No associations

Rating

The effect of alternative tree representations on tree bank grammars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The effect of alternative tree representations on tree bank grammars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The effect of alternative tree representations on tree bank grammars will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-66404