53. A ranking method comprising: executing a document ranking application on a processor to rank documents retrieved from a data source in response to a search request, the document ranking application comprising a term frequency module, a negation module, a ranking module, and a user interface module; querying the data source from the term frequency module to identify a plurality of documents that each comprises a key term, the key term matching a search term in the search request; determining a corresponding term frequency value for the key term in each of the plurality of documents at the term frequency module, the term frequency value comprising a total number of occurrences of the key term in a particular document; retrieving at least one negation term and the at least one negation rule from a memory using the negation module; comparing, at the negation module, the at least one negation term according to the at least one negation rule to other terms in each document that are within a selected proximity of each occurrence of the key term to determine if each occurrence of the key term has a negative context; determining that the at least one negation term matches another term within the selected proximity of the particular occurrence of the key term according to the at least one negation rule and excluding a particular occurrence of the key term in at least one document at the negation module for having the negative context; determining a corresponding term weight value for the key term in each document based on each occurrence of the key term that has not been excluded; determining a corresponding relevancy ranking value at the ranking module for each document based on the corresponding term frequency value and corresponding term weight value; and generating a list of document data for display at the user interface module, the list identifying each document of the plurality of documents in an order based on the corresponding relevancy ranking value of each document.
53. A ranking method comprising: executing a document ranking application on a processor to rank documents retrieved from a data source in response to a search request, the document ranking application comprising a term frequency module, a negation module, a ranking module, and a user interface module; querying the data source from the term frequency module to identify a plurality of documents that each comprises a key term, the key term matching a search term in the search request; determining a corresponding term frequency value for the key term in each of the plurality of documents at the term frequency module, the term frequency value comprising a total number of occurrences of the key term in a particular document; retrieving at least one negation term and the at least one negation rule from a memory using the negation module; comparing, at the negation module, the at least one negation term according to the at least one negation rule to other terms in each document that are within a selected proximity of each occurrence of the key term to determine if each occurrence of the key term has a negative context; determining that the at least one negation term matches another term within the selected proximity of the particular occurrence of the key term according to the at least one negation rule and excluding a particular occurrence of the key term in at least one document at the negation module for having the negative context; determining a corresponding term weight value for the key term in each document based on each occurrence of the key term that has not been excluded; determining a corresponding relevancy ranking value at the ranking module for each document based on the corresponding term frequency value and corresponding term weight value; and generating a list of document data for display at the user interface module, the list identifying each document of the plurality of documents in an order based on the corresponding relevancy ranking value of each document. 60. The method of claim 53 wherein retrieving the at least one negation rule comprises retrieving a suffix negation rule comprising that a suffix negation term appear after the key term in a same sentence as the key term within the selected proximity.