Extracting relationships from sentences

Knowing the relationship between elements of a sentence is important in many analysis tasks. It is useful for assessing the important content of a sentence and providing insight into the meaning of a sentence. This type of analysis has been used for tasks ranging from grammar checking to speech recognition to language translations.

In the previous section, we demonstrated one approach used to extract the parts of speech. Using this technique, we were able to identify the sentence element types present in a sentence. However, the relationships between these elements is missing. We need to parse the sentence to extract these relationships between sentence elements.

Using OpenNLP to extract relationships

There are several techniques and APIs that can be used to extract this type of information. In this section we will use OpenNLP to demonstrate one way of extracting the structure of a sentence. The demonstration is centered around the ParserTool class, which...