Estimators for correlation/association and their properties and assumptions.
Use when a linear function best describes the relationship between the variables.
Susceptible to outliers. Assumes a bivariate normal distribution.
Use when a monotonic function best describes the relationship between variables.
Use when a monotonic function best describes the relationship between the variables. Preferred instead of Spearman correlation because Kendall's tau is the difference between the probability that the two variables are in the same order, versus the probability that the two variables are in different orders.
Robust to outliers.