Section 4
The Regression Line
By Boundless
In the regression line equation the constant
![Thumbnail](../../../../../../figures.boundless-cdn.com/18388/square/cova-partitioning-variance.jpeg)
ANCOVA can be used to compare regression lines by testing the effect of a categorial value on a dependent variable, controlling the continuous covariate.
![Thumbnail](../../../../../../figures.boundless-cdn.com/18246/square/linrgs-regeq1.jpg)
The criteria for determining the least squares regression line is that the sum of the squared errors is made as small as possible.
![Thumbnail](../../../../../../figures.boundless-cdn.com/18257/raw/linear-regression.jpg)
Standard linear regression models with standard estimation techniques make a number of assumptions.
The slope of the best fit line tells us how the dependent variable
![Thumbnail](../../../../../../figures.boundless-cdn.com/18248/square/220px-francis-galton-1850s.jpeg)
Regression toward the mean says that if a variable is extreme on its 1st measurement, it will tend to be closer to the average on its 2nd.