18. The method of claim 17 , wherein said step of normalizing includes the steps of: defining a set of reference words; calculating a word pair relevancy for each reference word relative to the keyword; and calculating the normalized word pair relevancy measure based upon said word pair relevancy for each reference word relative to the keyword.
18. The method of claim 17 , wherein said step of normalizing includes the steps of: defining a set of reference words; calculating a word pair relevancy for each reference word relative to the keyword; and calculating the normalized word pair relevancy measure based upon said word pair relevancy for each reference word relative to the keyword. 19. The method of claim 18 , wherein said normalized word pair relevancy is defined as: s d , k ′ = s d , k - μ k ⁡ ( A ) σ k ⁡ ( A ) wherein , ⁢ μ k ⁡ ( A ) = 1  A  ⁢ ∑ a ∈ A ⁢ s a , k , and σ k ⁡ ( A ) = ( 1  A  ⁢ ∑ a ∈ A ⁢ s a , k 2 ) - ( 1  A  ⁢ ∑ a ∈ A ⁢ s a , k ) 2