Table 1 Absolute frequency 2-D contingency table for rainfall (R in mm) and depth to water table (WT, m, bgl) at well W 42 (village: Tishkhora) located in the flood plain of a morphodynamic system in a part of the Ganga basin of Northern India.

From: Assessment of natural groundwater reserve of a morphodynamic system using an information-based model in a part of Ganga basin, Northern India

 

WT (m, bgl)

Rainfall (R) in mm

i = 1

i = 2

i = 3

i = 4

Total

Pj

Log Pj

Pj log Pj

H (WT)

Rainfall(mm)

0–100

100–200

200–300

300–410

Marginal entropy

j = 1

0–2

11

3

2

0

16

0.615

−0.700

−0.431

0.961 bits

Obtained From the Eq. (5)

 

j = 2

2–4

7

2

0

1

10

0.385

−1.379

−0.530

 
 

j = 3

4–6

0

0

0

0

0

0.000

   
 

j = 4

6–8

0

0

0

0

0

0.000

   
 

j = 5

8–10

0

0

0

0

0

0.000

   
  

Total

18

5

2

1

26

    
  

Pi

0.692

0.192

0.077

0.038

     
  

Log Pi

−0.531

−2.379

−3.700

−4.700

     
  

Pi*Log Pi

−0.367

−0.457

−0.285

−0.181

     
  

H (R)

1.290 bits obtained from the Eq. (4)

        
  

Pi,j

0.423

0.115

0.077

0.000

     
   

0.269

0.077

0.000

0.038

     
   

0.000

0.000

0.000

0.000

     
   

0.000

0.000

0.000

0.000

     
   

0.000

0.000

0.000

0.000

     
  

Pi,j *Log Pi,j

−0.525

−0.359

−0.285

0.000

     
   

−0.510

−0.285

0.000

−0.181

     
   

0.000

0.000

0.000

0.000

     
   

0.000

0.000

0.000

0.000

     
   

0.000

0.000

0.000

0.000

     

Joint entropy

H (R, WT) = 

2.144 bits obtained from the Eq. (6)

         

Transformation

T (R, WT) = 

0.107 bits obtained from the Eq. (7)

         

Natural recharge (%)

R (%) = 

8.30 obtained from the Eq. (8)