Model fit statistics for the S-79 total phosphorus load models using all available data and excluding hurricane years.
Modela
R²
Adj R²
σb
F-Statistic
ρ-value
DOF(Model, Residuals)
Observations
All Data
0.80
0.78
49112
29.84
<0.01
3, 22
26
Hurricane Years Excluded
0.74
0.69
74805
14.90
3, 16
20
a Total Phosphorus Load Model (WY1982 - 2019)
b σ = Residual Standard Error
Models based on 70:30 train:test approach
S-79 total phosphorus model results and estimates fitted using all available data during the water year 1982 - 2019 period.
Estimate
Standard Error
t-value
(Intercept)
127,156.07
103,885.73
1.22
0.23
QC43
0.20
0.05
3.72
≤ 0.01
QS77
0.08
0.02
3.70
Mean Lake Stage
-7,689.38
9,172.09
-0.84
0.41
Residual standard error: 49112 on 22 degrees of freedom
Multiple R-squared: 0.80, Adjusted R-squared: 0.78
F-statistic: 29.84 on 22 and 3, ρ-value: ≤ 0.01
Parameter
Mean
Min
Max
Model
R2adj
0.71
0.62
0.79
RMSE
63,461
41,657
76,864
Train:Test
MAPE 1
21
16
41
MMA 1
83
78
86
1 Mean Absolute Percent Error (MAPE) and Min-Max Accuracy (MMA) expressed in percent
Model fit statistics for the S-79 total nitrogen load models using all available data and excluding hurricane years.
0.95
0.94
326435
140.19
0.93
410391
81.56
a Total Nitrogen Load Model (WY1982 - 2019)
S-79 total nitrogen model results and estimates fitted using all available data during the water year 1982 - 2019 period.
27,560.89
690,496.68
0.04
0.97
1.53
0.35
4.38
1.58
0.15
10.48
20,812.63
60,964.10
0.34
Residual standard error: 326435 on 22 degrees of freedom
Multiple R-squared: 0.95, Adjusted R-squared: 0.94
F-statistic: 140.2 on 22 and 3, ρ-value: ≤ 0.01
0.89
0.96
376,894
324,753
411,799
11
7
19
89
93
Month
Total Phosphorus(μg L⁻¹) a
Total Nitrogen(mg L⁻¹) a
Jan
97 ± 28 (58)
1.40 ± 0.36 (56)
Feb
89 ± 21 (49)
1.71 ± 2.54 (49)
Mar
93 ± 25 (54)
1.28 ± 0.32 (55)
Apr
102 ± 26 (51)
1.25 ± 0.62 (50)
May
129 ± 37 (55)
1.34 ± 0.26 (55)
Jun
179 ± 67 (49)
1.57 ± 0.57 (49)
Jul
179 ± 66 (56)
1.47 ± 0.28 (56)
Aug
166 ± 41 (55)
1.43 ± 0.18 (54)
Sep
161 ± 49 (53)
1.47 ± 0.24 (51)
Oct
128 ± 33 (50)
1.43 ± 0.19 (50)
Nov
109 ± 26 (56)
1.43 ± 0.27 (55)
Dec
97 ± 35 (46)
1.37 ± 0.22 (46)
a Mean ± Std Dev (N)
POR: Jan 1981 - April 2019
Station ID: S79
Data Source: SFWMD DBHydro
Root mean standard error for models and period of record estimates.
Estimate Method
RMSE 1
NS 2
TP Load
Model - All Data
45,177
Model - Hur. Ex.
66,908
0.75
POR Est.
73,439
0.64
TN Load
300,277
367,065
405,274
0.91
1 RMSE value for POR Est. calculated using observed values versus annual estimated values using monthly mean concentrations
2 NS = Nash-Sutcliffe coefficient