Models

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

ME

IDW

0.20

0.95

2.56

0.83

-1.2

5.97

-2.58

1.28

-4.56

0.3

-0.68

0.59

TREND

0.31       

0.72       

1.32       

5.33

0.40

0.64       

0.31       

0.72       

1.32       

5.33

0.40

0.64

OK

0.22

0.97

2.54

1.48

0.35

6.73

-2.23

2.66

-3.78

0.75

-0.65

0.58

SPLINE

0.42

1.16

3.65

2.59

1.27

9.98

-0.94

4.5

-3.3

1.02

-0.38

0.7

REGRESSION

0.32

1.04

2.3

0.36

-1.51

6.15

-3.56

-0.23

-6.09

-0.57

-0.75

0.7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MAE

IDW

0.84

1.56

4.46

5.34

6.84

11.41

12.68

9.98

6.47

3.1

1.52

1.15

TREND

1.06

2.09

5.24

6.10

6.34

11.89

10.93

8.44

7.53

3.17

1.67

1.33

OK

0.84

1.89

5

4.85

4.57

8.15

8.18

7.06

4.8

1.63

1.41

1.18

SPLINE

0.97

1.81

7.29

6.99

7.04

12.18

12.57

9.71

6.68

2.79

1.51

1.47

REGRESSION

1.05

1.98

4.94

5.86

5.03

7.46

6.07

4.6

7.41

2.92

1.72

1.3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RMSE

IDW

1.19

1.94

5.65

6.53

8.56

13.50

15.47

12.72

8.23

3.51

1.71

1.35

TREND

1.28

2.22

8.13

8.88

8.52

15.01

15.80

10.52

8.23

3.88

1.88

1.79

OK

1.18

2.16

6.16

6.21

5.54

10.78

9.75

8.62

6.05

2.18

1.65

1.37

SPLINE

2.22

8.13

8.88

8.52

15.01

15.80

10.52

8.23

3.88

1.88

1.79

2.22

REGRESSION

1.27

2.32

6.16

6.63

6.10

9.47

8.33

7.39

9.21

3.51

2.08

1.53

Table 3: Validation errors averaged across 13 test sites for the five interpolation methods in each month.