All my life i seem to interpret formulas incorrect. ive never really tried in school until now. ive been in college for awhile. i know im pathedic. Anyways, i have a relatively simple question. Forgive me because i dont know how to superscribe and XXXX i cant think of the terms. anyways. im donig hte least squares regression line.
E=sum in my equation.
S_x_y=E X_i Y_i
why do i multiply X*Y individually and then sum that entire row?
Why dont i multiply the sum of the X's times the sum of the Y's?
If anyone knows somewhere that i could work on interpretting formulas id appreciate it because it seems that it can be fixed rather quickly while it causes lots of grief.
Also, why sometimes does it show Yhat sub i = bsub0 +bsub1*Xsubi
whats the difference between sub i and sub 1? thanks