diff --git a/education/statistics/Correlation and Regression.md b/education/statistics/Correlation and Regression.md
index 4f93bbb..951e6f6 100644
--- a/education/statistics/Correlation and Regression.md	
+++ b/education/statistics/Correlation and Regression.md	
@@ -53,4 +53,6 @@ https://www.thoughtco.com/how-to-calculate-the-correlation-coefficient-3126228
 	- add the same number to every x or y value
 	- multiply each $x$ or $y$ value by a positive number
 - The correlation coefficient can be misleading in the presence of outliers or nonlinear association. 
-- $r$ only shows the strength of a linear relationship.
\ No newline at end of file
+- $r$ only shows the strength of a linear relationship.
+- High $r$ only indicates high correlation, not causation.
+- $r$ is not a linear, perfect scale. An $r$ of 0.8 does not mean twice as much linearity as an $r$ of 0.4
\ No newline at end of file