diff --git a/education/statistics/Correlation and Regression.md b/education/statistics/Correlation and Regression.md
index a29b604..f4db2e4 100644
--- a/education/statistics/Correlation and Regression.md	
+++ b/education/statistics/Correlation and Regression.md	
@@ -99,6 +99,13 @@ $$ \hat{y} = \frac{x-\bar{x}}{\sigma_x} * r * \sigma_y + \bar{y} $$
 - 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
 - There are two separate regression lines, one for predicting $y$ from $x$, and one for predicting $x$ from $y$
 - Do not extrapolate outside of the graph
+
+(Ch 12, stat 1040)
+Predicting a y value for a given x value can be calculated when given the regression equation.
+$$ y = mx + b $$
+Where $y$ is the predicted value, $m$ is the slope, x is the given val and the $b$ is the intercept. 
+$$ slope = \frac{r * \sigma_y}{\sigma_x} $$
+
 ### 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. 
 - The regression *fallacy* is contributing this to something other than chance error.
@@ -114,9 +121,13 @@ $$ \sqrt{1-r^2}(\sigma_y) $$
 - To approximate the R.M.S error for a scatter diagram, take a high value and a low value for a given $x$ coordinate, and divide by 4, because r.m.s error is within $2\sigma$ of either side of the line. 
 - 68% = $2\sigma$, 95% = $4\sigma$
 - RMS can help determine which observations are outliers. Typically if a value is more than *2 r.m.s* away from the prediction estimate, it is considered to be an outlier
+- The RMS error is only appropriate for homoscedastic scatter diagrams (football shape)
+
+- Heteroscedastic scatter diagrams should not be used to make a prediction, because they do not follow a football shape
+- Homoscedastic scatter diagrams can be used to make predictions, because they follow a football shape
+
+
 
-- Heteroscedastic scatter diagrams should not be used to make a prediction
-- homoscedastic scatter diagrams can be used to make predictions, because they follow
 ---
 # Terminology
 | Term | Definition |  |