Developed in partnership with the Lower Platte River Corridor Alliance and the Nebraska Environmental Trust
Model Form #1
log10(ATRR) =
- 2.194 + 0.6975 log10(TURB)
+ 0.4713 sin(2π D / 365)
- 0.9344 cos(2π D / 365)
where:
- ATRR is computed atrazine, in micrograms per liter
- TURB is turbidity, YSI model 6136, in formazin nephelometric units
- D is day of year, in the range of integers 1 through 365
Model Calibration
Basic Data
| Number of measurements: | 42 |
|---|---|
| Mean squared error: | 0.16 |
| Multiple R2: | 0.64 |
| Bias correction (smearing) factor: | 1.49 |
Explanatory Variables
| Variable | Value | Standard error |
|---|---|---|
| Intercept | -2.194 | 0.267 | log10(TURB) | 0.6975 | 0.1389 | sin(2π D / 365) | 0.4713 | 0.1008 | cos(2π D / 365) | -0.9344 | 0.2581 |
Correlation Matrix
| Intercept | log10(TURB) | sin(2π D / 365) | cos(2π D / 365) | |
|---|---|---|---|---|
| Intercept | 1 | -0.7089 | -0.0516 | 0.3875 |
| log10(TURB) | -0.7089 | 1 | 0.2151 | 0.3379 |
| sin(2π D / 365) | -0.0516 | 0.2151 | 1 | 0.1951 |
| cos(2π D / 365) | 0.3875 | 0.3379 | 0.1951 | 1 |
Reference
- Schaepe, Nathaniel J.; Soenksen, Philip J.; Rus, David L., 2014, Relations of water-quality constituent concentrations to surrogate measurements in the lower Platte River corridor, Nebraska, 2007 through 2011: U.S. Geological Survey Open-File Report 2014–1149, 16 p.