STA215H5 Lecture Notes - Lecture 8: Coral Reef, Standard Deviation, Covariance
Document Summary
Sta215 lecture 8. 1: the correlation measures the direction and strength of the linear relationship between two quantitative variables. May 27th 2019: thus there is a strong negative association depicted in the scatterplot, facts about correlation, 1. Correlation makes no distinction between explanatory and response variables. It makes no difference which variable you call x and which you call y in calculating the correlation: 2. Because r uses the standardized values of the observations, r does not change when we change the units of measurement of x, y, or both. The correlation r itself has no unit of measurement; it is just a number: 3. Positive r indicates positive association between the variables, and negative r indicates negative association: 4. The correlation r is always a number between 1 and 1. Values of r near 0 indicate a very weak linear relationship.
