Linear regression line in MATLAB scatter plot
least-squares, matlab, regression
Solution
Use the function `polyfit` to obtain the regression parameters. You can then evaluate the fitted values and calculate your residuals accordingly.
Basically `polyfit` performs least-squares regression for a specified degree N which, in your case will be 1 for straight line regression. The regression parameters are returned by the function and you can use the other function `polyval` to get the fitted values from the regression parameters
Problem
I am trying to get the residuals for the scatter plot of two variables. I could get the least squares linear regression line using `lsline` function of matlab. However, I want to get the residuals as well. How can I get this in matlab. For that I need to know the parameters `a` and `b` of the linear regression line ``` ax+b ```