diff --git a/education/statistics/Correlation and Regression.md b/education/statistics/Correlation and Regression.md index 444471f..cc649fb 100644 --- a/education/statistics/Correlation and Regression.md +++ b/education/statistics/Correlation and Regression.md @@ -87,5 +87,9 @@ Given a scatter diagram where the average of each set lies on the point $(75, 70 $$ slope = r(\frac{\sigma_y}{\sigma_x}) $$ - 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. -$$ z_x = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$ -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 +The below formula can be used to predict a y value given a 5 number summary of a set. +$$ \hat{y} = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$ +# Terminology +| Term | Definition | +| -- | -- | +| $\hat{y}$ | The predicted value |