NLTK - Conversations

Statement and Response Relationship:

Grace stores information from the conversations as statements. Each user's input (statement) get tagged with any number (please see the : NLTK Tagging methods) and mapped to possible responses.
Therefore each statement object has a reference, which links the user's input to a number of other input statements.

The response object has counter which looks for the terms of frequency (please see the : TF-IDF Algorithm you can also visit grace search engine TF-IDF implementation/ Ranking section ) this attribute indicates the number of times that statement has been given to response. This makes it possible for the bot to determine if a particular  response is more commonly used than another.