Logical validation, answer merging and witness selection a study in multi-stream question answering

  • Authors:
  • Ingo Glöckner;Sven Hartrumpf;Johannes Leveling

  • Affiliations:
  • FernUniversität in Hagen, Hagen, Germany;FernUniversität in Hagen, Hagen, Germany;FernUniversität in Hagen, Hagen, Germany

  • Venue:
  • Large Scale Semantic Access to Content (Text, Image, Video, and Sound)
  • Year:
  • 2007

Quantified Score

Hi-index 0.00

Visualization

Abstract

The paper presents an approach to multi-stream question answering (QA) using deep semantic parsing and logical validation for filtering answer candidates. A robust entailment check is accomplished by embedding the prover in a relaxation loop. Fallback strategies ensure a graceful degradation of performance in the case of parsing problems. The logical validity score is complemented by false-positive tests and heuristic quality indicators which also affect the selection of the most trusted answers. Separate criteria are used for choosing a suitable 'witness', i.e. a text passage which substantiates the answer. We present two experiments in which the method is applied for merging the results of various state-of-the-art QA systems. The evaluation demonstrates that the approach is applicable to heterogeneous QA streams -- in particular it improves results for a combination of precision-oriented and recall-oriented answer streams. The method automatically adapts to these characteristics of a QA system by learning parameters from a training sample.