vault backup: 2023-12-18 13:54:40

education/statistics/Correlation and Regression.md

@@ -83,12 +83,18 @@ Given a scatter diagram where the average of each set lies on the point $(75, 70
 ### The Regression Line/Least Squared Regression Line (LSRL)
 - This line has a more moderate slope than the SD line. it does not go through the peaks of the "football"
 - The regression line is *used to predict* the y variable when the x variable is given
-- The regression line also goes through the point of averages
+- The regression line goes through the point of averages
 $$ slope = r(\frac{\sigma_y}{\sigma_x}) $$
 - You can find the regression line by multiplying $\sigma_y$ by $r$, for the rise, then using $\sigma_x$ for the run from the point of averages.
 
 The below formula can be used to predict a y value given a 5 number summary of a set. 
 $$ \hat{y} = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$
+1. Find $z_x$
+2. Multiply $z_x$ by $r$
+3. Multiply that by $\sigma_y$
+4. Add the average of $y$
+
+
 # Terminology
 | Term | Definition |
 | -- | -- |