Hi Guys, Any help with this,please? Regards, Preetam On Thu, Jan 5, 2017 at 4:09 AM, Preetam Pal <lordpree...@gmail.com> wrote:
> Hello guys, > > The context is ordinary multivariate regression with k (>1) regressors, > i.e. *Y = XB + Error*, where > Y = n X 1 vector of predicted variable, > X = n X (k + 1) matrix of regressor variables(including ones in the first > column) > B = (k+1) vector of coefficients, including intercept. > > Say, I have already estimated B as B_hat = (X'X)^(-1) X'Y. > > I have to solve the following program: > > *minimize f(B) = LB* ( L is a fixed vector 1 X (k+1) ) > such that: > *[(B-B_hat)' * X'X * (B-B_hat) ] / [ ( Y - XB_hat)' (Y - XB_hat) ] * is > less than a given value *c*. > > Note that this is a linear optimization program *with respect to B* with > quadratic constraints. > > I don't understand how we can solve this optimization - I was going > through some online resources, each of which involve manually computing > gradients of the objective as well as constraint functions - which I want > to avoid (at least manually doing this). > > > Can you please help with solving this optimization problem? The inputs > would be: > > - X and Y > - B_hat > - L > - c > > > Please let me know if any further information is required - the set-up is > pretty general. > > Regards, > Preetam > -- Preetam Pal (+91)-9432212774 M-Stat 2nd Year, Room No. N-114 Statistics Division, C.V.Raman Hall Indian Statistical Institute, B.H.O.S. Kolkata. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.