I need to run a multiple regression in some limited software that cannot preform any matrix calculations. I am not so good at deriving these on my own and would love some assistance.
I need something similar to these 2 walkthroughs but for a model containing 3 input variables.
https://www.statology.org/multiple-linear-regression-by-hand/
https://www.statology.org/linear-regression-by-hand/
Ex: for simple linear regression b0 = [(ΣY)(ΣX2) – (ΣX)(ΣXY)] / [n(ΣX2) – (ΣX)2] Something like this but for all coefficients for a model with 3 input variables and an intercept.