113 Math
113.033 Statistics - Residuals


Residual is the y-axis distance between where a point actually is and where the linear regression line crosses the y-axis for that x-value.
- E.g. if the point was (3,8) and the linear regression line crosses at the point (3,10) then the Residual == -2
- Residuals help us measure the line of best fit through a scatterplot
- $$r_i = y_i - \hat{y}$$
- Reads: The residual of a point i equals the actual y value at point i, minus the predicted regression line value at point i

  • statistics