Model Form #1
log10(TP) =
- 2.253 + 0.468 log10(TURB)
+ 0.217 log10(Q)
+ 0.00881 cos(2π D / 365)
- 0.137 sin(2π D / 365)
where:
- TP is computed total phosphorus, in milligrams per liter as phosphorus
- TURB is turbidity, YSI model 6136, in formazin nephelometric units
- Q is computed discharge, stage-discharge rating curve, in cubic feet per second
- D is day of year, in the range of integers 1 through 365
Model Calibration
Basic Data
| Number of measurements: | 84 |
|---|---|
| Mean squared error: | 0.013924 |
| Multiple R2: | 0.739 |
| Bias correction (smearing) factor: | 1.57426 |
Explanatory Variables
| Variable | Value | Standard error |
|---|---|---|
| Intercept | -2.253 | 0.118 | log10(TURB) | 0.468 | 0.0376 | log10(Q) | 0.217 | 0.0489 | cos(2π D / 365) | 0.00881 | 0.035 | sin(2π D / 365) | -0.137 | 0.0214 |
Correlation Matrix
A correlation matrix is not available for this model. Therefore, the prediction interval was calculated by assuming that there is no correlation between the explanatory variables.
Reference
- Galloway, J., 2014, Continuous Water-Quality Monitoring and Regression Analysis to Estimate Constituent Concentrations and Loads in the Red River of the North at Fargo and Grand Forks, North Dakota, 2003–12: U.S. Geological Survey Scientific Investigations Report 2014–5064, 37 p.