In a linear model, the effect of a change in the independent variable is the same at all levels of the independent variable.
The true line and a regression line.
Least squares regression illustrated. Least squares regression with true line with 0 slope.
Bias concept illustrated
Efficiency comparison between connect-the-end-points and least squares regression.
Students' eyeball lines and least squares lines compared
Normal distribution of the error illustrated, using discreet values of X..
Normal distribution of the error illustrated, using continuous values of X.
Scatter of points from log(Y)=log(A)+b log(X)+normal error
Random error can produce a Type I error
Queue simulation for live demonstration