PLIS - a Probabilistic Lexical Inference System


The PLIS download package contains the following folders:

The PLIS, BIU and EXCITEMENT code is available under the GPL version 3. The resources are available under various licenses. Please read and agree to the license of each resource.

To install and run PLIS you will need to have:

Install the source code:

Assuming that you use the Eclipse IDE:
  1. Install the Maven2Eclipse (M2E) plugin, from this repository: (copy this link and paste in Help-->Install New Software-->Work with>).
  2. In Eclipse, go to File->Import->Maven->Existing Maven Project, select the "workspace" folder, and import all projects.
  3. Make sure your workspace contains the following projects: common, core, Excitement-Open-Platform, factories, infrastructure_remains, lap, lexical_inference, lexical_integrator, parse.
  4. For each project except Excitement-Open-Platform, open it in the Package Explorer, right-click "JRE System Library", select "Properties", and change the "Execution environment" to Java SE 1.7 (this is a workaround for a bug in M2E plugin).
  5. If there are compilation errors, try Project -> Clean -> Clean all projects.

The lexical_integrator package

Here you will find the code that integrates various input lexical resources in a lexical graph data structure (notes are terms and edges are inference rules). Paths can be extracted from this graph to deduce lexical relations between source and target terms.
The entry point to this package is LexicalResourcesIntegrator which has a main method that demonstrates a common usage:
  1. Go to the class LexicalResourcesIntegrator.
  2. Run as -> Java application. You should see several paths that link a source word to a target word.
  3. A configuration file defines the system configuration for this example. It can be easily edited. For instance, choosing which lexical resources to use as input is done through the parameter "lexical resources". The file location is: src/main/java/configuration/lexResIntegr_config.xml

The lexical_inference package

This package adds the layer of Probabilistic Lexical Model (PLM) on top of the Lexical Integrator. This project include the various models developed to estimate that reliability level of input lexical resources and to estimate the entailment probability of each rule step, inference chain and full Text to Hypothesis inference.
Using this package spare the user the need to handle the lower level of the Lexical integrator. This package encapsulates LexicalResourcesIntegrator and the user just use its API.
The important (abstract) class of this package is PLM (Probabilistic Lexical Model). It implements the inference process (including learning). The provided probabilistic models, as well as any new model the user would like to add, should extend this class.
A suggested entry point for new users is the examples with detailed explanations (under ac.biu.nlp.demo.examples):
  1. Go to the class PLMfullSentencesExample.
  2. Run as -> Java application. You should see several lexical inference chains with probability estimations.
  3. The configuration file location for this example is: src/main/java/configuration/lexResInferExampleCode_config_local.xml

Install additional resources

There are several MySQL-based lexical resources, which you can install using the following links:

Schema NameConfiguration ModuleMySQL SchemaFile Size
BAP (Directional Similarity)DIRECTDownload111 MB
Lin SimilarityDistSimDownload236 MB
Wikipedia Knowledge ResourceWikipediaDownload214 MB

After you download the Schema, use MySQL WorkBenchServer AdministrationData Import to import them to your databases.

Then change the relevant configuration modules in the configuration file, and insert the correct MySQL connection string.

Further Reading

The PLIS system and its probabilitsic models are explained in the following papers: