So how would I use the lm() to estimate b_0 and b_1 for example???? My Y_i and Y_j are data observations how does the lm() use my data.frame ? -- View this message in context: http://r.789695.n4.nabble.com/OLS-Estimating-tp4580055p4581048.html Sent from the R help mailing list archive at Nabble.com.