Linear regression with Excel

Excel is a convenient tool, though often not so useful for science.

If you want to obtain a proper linear regression and r^2 values, don't use trend line from the GUI. Instead,

=index(linest(y's, x's, false, true),1) for slope

=index(linest(y's, x's, false, true),2) for y-intersect

=index(linest(y's, x's, false, true),3) for r^2