From 5caa33ab6264635fc939403e2517c9f049481530 Mon Sep 17 00:00:00 2001 From: zleyyij Date: Fri, 15 Dec 2023 13:24:23 -0700 Subject: [PATCH] vault backup: 2023-12-15 13:24:23 --- education/statistics/Correlation and Regression.md | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/education/statistics/Correlation and Regression.md b/education/statistics/Correlation and Regression.md index 8bbf158..8dd2b5b 100644 --- a/education/statistics/Correlation and Regression.md +++ b/education/statistics/Correlation and Regression.md @@ -86,4 +86,7 @@ Given a scatter diagram where the average of each set lies on the point $(75, 70 - The regression line also 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. -$$ z_x = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$ \ No newline at end of file + + +$$ z_x = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$ +This formula finds the $z$ score for $x$, transforms by $r$, and uses the equation $x = z * \sigma + \bar{x}$ to predict a value for one axis given another axis. \ No newline at end of file