Patent ID: 11960521
Assignee: nan
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 1:
2. The text classification method based on feature selection according to claim 1, wherein the improved chi-square statistical formula is:

IMP_CHI(t,ci)=x2(t,ci)×α(t,cj)×β×γ

where α(t,cj) is a word frequency adjustment parameter, β is an intra-category position parameter, γ is a negative correlation correction factor, and x2(t,ci) is a traditional chi-square statistical formula, which is expressed as:, x
    2
   
   (
   
    t
    ,
    
     c
     i
    
   
   )
  
  =
  
   
    N
    ×
    
     
      (
      
       
        A
        ×
        D
       
       -
       
        C
        ×
        B
       
      
      )
     
     2
    
   
   
    
     (
     
      A
      +
      C
     
     )
    
    ×
    
     (
     
      B
      +
      D
     
     )
    
    ×
    
     (
     
      A
      +
      B
     
     )
    
    ×
    
     (
     
      C
      +
      D
     
     )
    
   
  
 

where N represents the total number of all texts in the training test set, A is a text belonging to the category ci and containing the feature word t, B is a text not belonging to the category ci and containing the feature t, C is a text belonging to the category ci and not containing the feature word t, and D is a text not belonging to the category ci and not containing the feature word t;
for multi-category problems, a statistical calculation method of the feature word with respect to the whole training text set is expressed as:

IMP_CHImax(t)=maxj=1m{IMP_CHI(t,cj)}

where m is the number of categories.