Compute a linear equation between two or more variables
Are the two variables
correlated (no equation)?
Parametric Approach: Pearson's r. Assumes
linear relationship. See chap. 8.
Nonparametric Approach. Spearman's rho or
Kendall's tau. See chap. 8.
What is the equation when
there is one X variable?
Parametric Approach: Linear Regression.
Assumes residuals follow a normal distribution. See chapter
9
Nonparametric Approach. Kendall-Theil
robust line. Assumes linear relationship, but does not
require normal residuals. See chapter 10.
What is the equation when
there is multiple X variables?
Parametric Approach: Multiple Regression.
Assumes residuals follow a normal distribution. See chapter
11
Nonparametric Approach. Kendall-Theil
robust line relating residuals of Y version some X
variables versus the remaining X variable. Assumes linear
relationship, but does not require normal residuals. See
chapter 12.
Chapter references are to the course textbook Statistical Methods in Water
Resources.