Associate
- Joined
- 9 Aug 2006
- Posts
- 753
- Location
- UK
Hi,
Im normally managing to deal with the maths problems one way or another but this time, Im just getting nowhere and thought of trying my luck to see if anyone here is into Econometrics. Anyway, Im wondering if anyone could help me with the RSS(Residual Sum of Squares). I generally know that:
RSS = Sum (Y - Y^estimated)^2
but I had a question with initial model Y=alpha + betaX for which the estimated Y is not known and I only got the final figure for the RSS so I do not know how exactly it was calculated.
I found another formula which is:
RSS = SumY^2 - n(mean_Y)^2 - beta(Sum XY - n(mean_X)(mean_Y))
where n = sample size and beta = the estimation of one of the coefficients.
Nevertheless this one didnt work for me to match the already given answer so I am wondering if anyone might by any chance have some info on this. Is there something I am missing or maybe the formula is correct but the final figure I am given is wrong?
Im normally managing to deal with the maths problems one way or another but this time, Im just getting nowhere and thought of trying my luck to see if anyone here is into Econometrics. Anyway, Im wondering if anyone could help me with the RSS(Residual Sum of Squares). I generally know that:
RSS = Sum (Y - Y^estimated)^2
but I had a question with initial model Y=alpha + betaX for which the estimated Y is not known and I only got the final figure for the RSS so I do not know how exactly it was calculated.
I found another formula which is:
RSS = SumY^2 - n(mean_Y)^2 - beta(Sum XY - n(mean_X)(mean_Y))
where n = sample size and beta = the estimation of one of the coefficients.
Nevertheless this one didnt work for me to match the already given answer so I am wondering if anyone might by any chance have some info on this. Is there something I am missing or maybe the formula is correct but the final figure I am given is wrong?