In Regression w/ Dummy Variables by Melissa A Hardy she reviews Multiple Regression and recommends the reader have a grasp on single-equation regression, partialing and hypothesis testing.
– Linear Regression
– Hypothesis Testing
– I think she’s referring to partial differentiation
Jason Delany: Simple Linear Regression YouTube Playlist
Khan Academy Least Squares Videos
– Least squares approximation
– Least squares examples
– Uses matrices and linear algebra
— Matrix equations
— Matrices for solving systems of eqns
– Linear Regression & Correlation
Dawn E. Wright, Ph.D. posted a list of regression related video links.