
SEA Working Paper 00/12
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Explaining groundwater hydrographs: separating atypical rainfall events from time trends
Ruhi FerdowsianA, David J. PannellB , Clare McCarronA, Arjen RyderA and Lisa CrossingA
AAgriculture
Western Australia, Albany WA 6330, Australia.
BFaculty of Agriculture, University of
Western Australia, Perth, WA 6907, Australia.
Tables
Table 1. Results of OLS estimations
Rainfall (m/mm) |
Month (m/month) |
|||||||
Bore no |
Rainfall variable |
Lag (L) (months) |
Constant (K0) (m)** |
Parameter estimate (K1) |
P |
Parameter estimate (K2) |
P |
R2 |
1 |
AMRR |
28 |
-18.7 |
0.0024 |
0.000 |
0.018 |
0.000 |
0.93 |
2* |
AMRR |
28 |
-18.2 |
0.0007 |
0.000 |
0.018 |
0.000 |
0.99 |
3* |
AMRR |
10 |
-18.3 |
0.0004 |
0.042 |
0.012 |
0.000 |
0.95 |
4 |
AARR |
7 |
-17.1 |
0.0013 |
0.181 |
0.017 |
0.000 |
0.63 |
5 |
AMRR |
46 |
-15.6 |
0.0033 |
0.007 |
0.028 |
0.000 |
0.87 |
6 |
AMRR |
14 |
-13.8 |
0.0016 |
0.000 |
0.025 |
0.000 |
0.91 |
7 |
AMRR |
17 |
-12.8 |
0.0022 |
0.000 |
0.022 |
0.000 |
0.97 |
8 |
AARR |
1 |
-13.5 |
0.0016 |
0.000 |
0.013 |
0.000 |
0.90 |
9* |
AMRR |
27 |
-12.5 |
0.0005 |
0.000 |
0.011 |
0.000 |
0.97 |
10 |
AMRR |
11 |
-11.4 |
0.0019 |
0.000 |
0.027 |
0.000 |
0.98 |
11 |
AMRR |
7 |
-8.2 |
0.0040 |
0.000 |
0.007 |
0.000 |
0.79 |
12 |
AMRR |
6 |
-7.8 |
0.0036 |
0.000 |
0.016 |
0.000 |
0.95 |
13 |
AMRR |
1 |
-6.4 |
0.0033 |
0.008 |
0.015 |
0.000 |
0.73 |
14 |
AMRR |
17 |
-5.9 |
0.0005 |
0.357 |
0.017 |
0.000 |
0.90 |
15 |
AMRR |
3 |
-5.7 |
0.0031 |
0.000 |
0.001 |
0.248 |
0.91 |
16 |
AMRR |
6 |
-4.9 |
0.0035 |
0.000 |
0.005 |
0.006 |
0.62 |
17 |
AMRR |
3 |
-5.5 |
0.0034 |
0.000 |
0.023 |
0.000 |
0.91 |
18 |
AMRR |
2 |
-5.2 |
0.0019 |
0.000 |
0.008 |
0.000 |
0.80 |
19 |
AMRR |
4 |
-5.0 |
0.0007 |
0.033 |
0.015 |
0.000 |
0.92 |
20 |
AMRR |
0 |
-3.2 |
0.0020 |
0.066 |
0.015 |
0.000 |
0.48 |
21* |
AMRR |
3 |
-4.1 |
0.0032 |
0.000 |
-0.005 |
0.001 |
0.72 |
22 |
AMRR |
0 |
-3.5 |
0.0053 |
0.000 |
-0.007 |
0.000 |
0.80 |
23 |
AMRR |
1 |
-3.5 |
0.0041 |
0.000 |
-0.014 |
0.000 |
0.86 |
24 |
AMRR |
0 |
-3.3 |
0.0061 |
0.000 |
-0.001 |
0.683 |
0.84 |
25 |
AMRR |
6 |
-2.8 |
0.0048 |
0.000 |
0.020 |
0.000 |
0.96 |
26 |
AMRR |
0 |
-3.7 |
0.0060 |
0.000 |
-0.016 |
0.000 |
0.82 |
27 |
AMRR |
5 |
-3.2 |
0.0008 |
0.000 |
0.002 |
0.000 |
0.54 |
28 |
AMRR |
0 |
-2.8 |
0.0024 |
0.000 |
0.012 |
0.000 |
0.79 |
29 |
AMRR |
1 |
-2.6 |
0.0014 |
0.001 |
0.005 |
0.000 |
0.54 |
30 |
AARR |
0 |
-2.2 |
0.0015 |
0.096 |
0.011 |
0.000 |
0.45 |
31* |
AMRR |
3 |
-2.3 |
0.0036 |
0.000 |
-0.005 |
0.002 |
0.77 |
32 |
AMRR |
1 |
-1.4 |
0.0015 |
0.014 |
0.007 |
0.001 |
0.36 |
33 |
AARR |
0 |
-2.0 |
0.0010 |
0.098 |
0.001 |
0.390 |
0.09 |
34 |
AMRR |
0 |
-1.9 |
0.0011 |
0.035 |
0.000 |
0.843 |
0.20 |
35 |
AMRR |
0 |
-1.5 |
0.0021 |
0.030 |
0.000 |
0.844 |
0.17 |
36 |
AMRR |
0 |
-0.5 |
0.0008 |
0.277 |
-0.001 |
0.525 |
0.11 |
37 |
AARR |
0 |
-1.4 |
0.0006 |
0.015 |
0.003 |
0.000 |
0.46 |
38 |
AMRR |
1 |
-1.0 |
0.0016 |
0.009 |
0.001 |
0.505 |
0.34 |
39 |
AMRR |
1 |
-1.0 |
0.0028 |
0.000 |
0.003 |
0.024 |
0.78 |
40* |
AARR |
1 |
-1.1 |
0.0024 |
0.000 |
-0.003 |
0.002 |
0.71 |
41 |
AARR |
0 |
-0.8 |
0.0024 |
0.011 |
-0.006 |
0.045 |
0.41 |
42 |
AMRR |
0 |
-1.4 |
0.0020 |
0.000 |
0.003 |
0.089 |
0.40 |
43 |
AMRR |
0 |
-0.2 |
0.0035 |
0.005 |
-0.012 |
0.010 |
0.61 |
44 |
AMRR |
0 |
-0.4 |
0.0018 |
0.000 |
0.005 |
0.016 |
0.58 |
45 |
AARR |
0 |
-1.2 |
0.0026 |
0.024 |
-0.003 |
0.542 |
0.36 |
46 |
AARR |
0 |
-0.9 |
0.0016 |
0.170 |
-0.009 |
0.093 |
0.34 |
47 |
AMRR |
0 |
-0.6 |
0.0005 |
0.272 |
-0.002 |
0.127 |
0.15 |
48 |
AARR |
0 |
-0.2 |
0.0018 |
0.000 |
-0.004 |
0.006 |
0.55 |
49 |
AMRR |
0 |
-0.3 |
0.0007 |
0.006 |
0.000 |
0.663 |
0.25 |
*, Bores in Tertiary sand plain;
**, constant is approximately equal to initial depth to groundwater.
Table 2. Diagnostic test results for OLS models
Bore no |
Omitted variable test |
Heteroskedasticity test |
Durbin-Watson statistic |
|||
1 |
0.021 |
* | 0.091 |
1.13 |
++ | |
2 |
0.052 |
0.021 |
* | 1.07 |
++ | |
3 |
0.792 |
0.104 |
1.47 |
+ | ||
4 |
0.799 |
0.054 |
2.14 |
|||
5 |
0.000 |
* | 0.082 |
0.53 |
++ | |
6 |
0.466 |
0.000 |
* | 1.37 |
++ | |
7 |
0.001 |
* | 0.645 |
0.88 |
++ | |
8 |
0.003 |
* | 0.022 |
* | 1.02 |
++ |
9 |
0.222 |
0.562 |
1.57 |
+ | ||
10 |
0.000 |
* | 0.550 |
0.54 |
++ | |
11 |
0.438 |
0.947 |
1.09 |
++ | ||
12 |
0.001 |
* | 0.001 |
* | 1.44 |
+ |
13 |
0.000 |
* | 0.789 |
0.39 |
++ | |
14 |
0.336 |
0.001 |
* | 0.17 |
++ | |
15 |
0.282 |
0.011 |
* | 1.23 |
++ | |
16 |
0.556 |
0.289 |
1.53 |
+ | ||
17 |
0.288 |
0.676 |
1.71 |
|||
18 |
0.173 |
0.740 |
0.81 |
++ | ||
19 |
0.743 |
0.752 |
1.83 |
|||
20 |
0.059 |
0.039 |
* | 1.13 |
++ | |
21 |
0.577 |
0.997 |
0.79 |
++ | ||
22 |
0.152 |
0.400 |
0.72 |
++ | ||
23 |
0.115 |
0.001 |
* | 0.33 |
++ | |
24 |
0.823 |
0.448 |
1.58 |
+ | ||
25 |
0.963 |
0.707 |
1.19 |
++ | ||
26 |
0.003 |
* | 0.831 |
0.89 |
++ | |
27 |
0.261 |
0.457 |
1.16 |
++ | ||
28 |
0.011 |
* | 0.304 |
0.80 |
++ | |
29 |
0.116 |
0.959 |
0.83 |
++ | ||
30 |
0.170 |
0.450 |
0.79 |
++ | ||
31 |
0.175 |
0.965 |
1.44 |
+ | ||
32 |
0.303 |
0.001 |
* | 1.33 |
++ | |
33 |
0.755 |
0.020 |
* | 1.96 |
||
34 |
0.400 |
0.418 |
0.58 |
++ | ||
35 |
0.325 |
0.849 |
0.74 |
++ | ||
36 |
0.515 |
0.011 |
* | 0.41 |
++ | |
37 |
0.790 |
0.213 |
0.75 |
++ | ||
38 |
0.029 |
* | 0.334 |
1.66 |
||
39 |
0.432 |
0.827 |
0.40 |
++ | ||
40 |
0.809 |
0.880 |
0.55 |
++ | ||
41 |
0.410 |
0.139 |
0.29 |
++ | ||
42 |
0.576 |
0.758 |
1.00 |
++ | ||
43 |
0.542 |
0.803 |
0.49 |
++ | ||
44 |
0.208 |
0.609 |
1.87 |
|||
45 |
0.600 |
0.615 |
0.81 |
++ | ||
46 |
0.000 |
* | 0.552 |
0.34 |
++ | |
47 |
0.041 |
* | 0.402 |
1.06 |
++ | |
48 |
0.184 |
0.141 |
1.46 |
|||
49 |
0.974 |
0.794 |
1.20 |
++ | ||
*, Below critical value of 0.05;
+, below upper critical value of 1.62 (i.e. rejection of H0 of no serial correlation is not clear);
++, below lower critical value of 1.44 (i.e. reject H0 of no serial correlation, with P = 0.05).
Table 3. Results of PRAIS estimations
Rainfall variable (m/mm) |
Month (m/month) |
|||||||
Bore no |
Constant (K0) (m) |
Parameter estimate (K1) |
p |
Parameter estimate (K2) |
p |
R2 |
Durbin-Watson statistic |
|
1 |
-18.7 |
0.0026 |
0.000 |
0.052 |
0.000 |
0.99 |
1.63 |
|
2 |
-18.2 |
0.0007 |
0.000 |
0.053 |
0.000 |
1.00 |
1.67 |
|
3 |
-18.3 |
0.0004 |
0.051 |
0.036 |
0.000 |
0.99 |
1.52 |
+ |
4 |
-17.1 |
0.0007 |
0.374 |
0.049 |
0.000 |
0.97 |
1.79 |
|
5 |
-15.7 |
0.0033 |
0.003 |
0.082 |
0.000 |
0.99 |
1.15 |
++ |
6 |
-13.9 |
0.0017 |
0.000 |
0.078 |
0.000 |
1.00 |
1.29 |
++ |
7 |
-12.8 |
0.0021 |
0.000 |
0.066 |
0.000 |
1.00 |
1.80 |
|
8 |
-13.5 |
0.0015 |
0.000 |
0.036 |
0.000 |
0.99 |
1.44 |
+ |
9 |
-12.5 |
0.0005 |
0.001 |
0.032 |
0.000 |
0.99 |
1.84 |
|
10 |
-11.5 |
0.0020 |
0.000 |
0.079 |
0.000 |
|||