a) Demonstrate the units conversion computation for the first now in the table (i.e., that 15.8 ib/ac - in. with a runoff of 0.024 in. results in 12.4 Ib of SS).
b) Rainfall is to be considered as an explanatory varibale (independnet varibale) for the predication of runoff, SS (Ib), and SS (ib/ac.in.) Perform the three indicated linear regressios. Test the siginifinace of the regressions at the 95% level (alpha = 5%). Plot the data poitns for runoff vs. rainfall on one graph and for both SS values vs. rainfall on one or two other graph. If the regression is siginificnat, include the predictaed stragigh line.
Althourgh yoru software may test the siginifance automatically, list the "table" T - value that must be exceeded for the regression to be significant. Obtain this value from a statistics book.
c) What other causative factors (that would very with each storm) might be included in a multiple linear regression of runoff vs. rainfall (depths)?
This problem illsutrates an example of "spurious correlation" for the SS vs. rainfall data. Load is the product of a constant x runoff depth x conecntration. Since runoff is correlated with rainfall, the dependent variable (load "inculdes" ranifall as part of its value. Hence, load will always correlate better with rainfall than will concentration?