PLIS: a Probabilistic Lexical Inference System

PLIS is an open source Probabilistic Lexical Inference System which combines two functionalities:

  • A tool for integrating lexical inference knowledge from diverse resources (e.g. WordNet, WikiRules!)
  • A framework for scoring textual inferences based on the integrated knowledge. PLIS is provided with several probabilistic implementation of this framework.

Developers of text processing applications can use PLIS as an off-the-shelf component for injecting lexical knowledge into their applications.
PLIS is easily configurable, components can be extended or replaced with user generated ones to enable system customization.


PLIS has an online interactive viewer, which is a powerful tool for investigating lexical inference processes.
Just enter a Text and a Hypotheis, choose your knowledge resources, set a transitivity limit and get the entailment probability.

Related Publications

PLIS interactive viewer (PLIS demo) is presented in:

  • Eyal Shnarch, Erel Segal Halevi, Jacob Goldberger, Ido Dagan. PLIS: a Probabilistic Lexical Inference System. ACL (Demonstration), 2013.

The probabilistic lexical models implemented within PLIS are described in the following papers:

All papers can be found here.

Download PLIS

Download PLIS package here and follow the installation instructions in the README file.


Contact: Eyal Shnarch, shey @