Glossary

Corpus

A corpus is a set of documents. TextChart Studio allows a user to save the file paths to multiple corpora on the Corpus Management page.

Entity

Entities are the important items such as persons, places, and events that TextChart finds within a document. The linguistic context of the document determines what words or phrases are extracted as entities.

Users have the ability to modify entity extraction results and to apply their own real-world knowledge. The LxBase documentation includes a list of all the types of entities that TextChart can extract.

GxBase

TextChart uses GxBase to retrieve the place names and geocoordinates that it finds in a set of documents. It uses the National Geospatial Agency's GNS and the United States Geological Survey's GNIS, as well as i2's own, internally developed gazetteer, to provide world-wide coverage and use linguistic context to decipher between ambiguous location names.

Through TextChart Studio, users can customize and import their own client-specific features.

LxBase

The LxBase is the set of underlying linguistic rules and dictionaries that TextChart uses as the foundation for entity and relationship extraction.

TextChart Studio allows users to modify and add to the LxBase in order to fine tune for industry-specific extraction goals.

Normalized form

Whether one term is equivalent to another is sometimes a choice for an individual user. For example, it might or might not be appropriate for the terms "Britain" and "England" to be considered equivalent to "United Kingdom".

When they do judge terms to be equivalent, users can arrange for TextChart to extract entities in the same, normalized form.

The standard TextChart dictionaries already contain many normalized lexical entries. Through TextChart Studio, users can modify and add normalized forms of their own. See Normalization management for more information.

Relationship (or PSO)

A predicate-subject-object statement, or PSO, is a relationship between two entities established by the linguistic context.

Relationships have names of the form EntityToEntity. For example, PersonToPerson is the name of a relationship between one person entity and another.

In TextChart, every relationship has a predicate that describes the nature of that relationship. For example, a PersonToPerson relationship might have the predicate "interviewed". For a full list of predicate types, see the LxBase documentation.

Semantic vector (or SV)

Semantic vectors represent a vector space of possible meanings for individual terms or phrases, allowing the same term to have various meanings depending on the linguistic context.

For example, a term such as "Washington" has many different semantic vectors associated with it: it might be a city name, a given name, or a surname. Some linguistic rules might even determine that it is a place.

In TextChart Studio, you can find (and modify) a list of semantic vectors and their corresponding definitions through the Token Definition Editor.

Token

A token is the smallest unit of meaning that TextChart can extract from a document.

For example, a TextChart dictionary might include the term "bank" as a noun, while the term "Bank of America" is an ORG. TextChart then considers both terms as one token, because they are both listed in the dictionary.

If "Bank of America" was not listed in the dictionary, then each unit of meaning would be parsed individually, resulting in three unique tokens: "Bank", "of", and "America".

You can modify this in TextChart Studio.