In the first case, there is a strong upward-sloping relationship between X and Y; in the second case, no apparent relationship; in the third case, a strong downward-sloping relationship. Note the ...

Correlation coefficients are indicators of the strength of the linear relationship between two different variables, x and y. A linear correlation coefficient that is greater than zero indicates a ...

Correlation doesn't imply causation. You've probably heard that before. It's a true statement that's important in statistical analysis—if more tall people own cats, that doesn't mean that cats cause ...