Table 5. Measures of the degree of map correlation, depending on measurement
(after Bonham-Carter, 1994)
| 
            | 
    
         Nominal  | 
    
         Ordinal  | 
    
         Interval/Ratio  | 
  
| 
         Nominal  | 
    
         Chi square, Kappa, Odds ratio, Contrast weight,
      etc.  | 
    
         Median by nominal class  | 
    
         Mean by nominal class  | 
  
| 
         Ordinal  | 
    
            | 
    
         Rank correlation coefficient  | 
    
         Rank correlation coefficient  | 
  
| 
         Interval/Ratio  | 
    
            | 
    
            | 
    
         Covariance, Correlation coefficient  |