A System for Adaptive Information Extraction from Highly Informal Text

摘要

We present a first version of ADO, a system for Adaptive Data Organization, that is, information extraction from highly informal text: short text messages, classified ads, tweets, etc. It is built on a modular architecture that integrates in a transparent way off-the-shelf NLP tools, general procedures on strings and machine learning and processes tailored to a domain. The system is called adaptive because it implements a semi-supervised approach. Knowledge resources are initially built by hand, and they are updated automatically by feeds from the corpus. This allows ADO to adapt to the rapidly changing user-generated language. In order to estimate the impact of future developments, we have carried out an orientative evaluation of the system with a small corpus of classified advertisements of the real estate domain in Spanish. This evaluation shows that tokenization and chunking can be well resolved by simple techniques, but normalization, morphosyntactic and semantic tagging require either more complex techniques or a bigger training corpus.