vault backup: 2023-12-18 14:19:40

education/statistics/Correlation and Regression.md

@@ -96,7 +96,8 @@ $$ \hat{y} = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$
 4. Add the average of $y$
 
 - For a positive association, for every $\sigma_x$ above average we are in $x$, the line predicts $y$ to be $\sigma_y$ standard deviations above y.x
-
+### The Regression Effect
+In a test-retest situation, people with low scores tend to improve, and people with high scores tend to do worse. This means that individuals score closer to the average as they retest. 
 # Terminology
 | Term | Definition |
 | -- | -- |