Re: please solve
- To: mathgroup at smc.vnet.net
- Subject: [mg52944] Re: please solve
- From: "Robert M. Mazo" <mazo at uoregon.edu>
- Date: Fri, 17 Dec 2004 05:19:32 -0500 (EST)
- Organization: University of Oregon
- References: <cprk0m$r87$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
On Thu, 16 Dec 2004 09:20:22 +0000 (UTC), rcmcll at yahoo.com wrote: >Greetings: > >Could someone please solve this symbolically? >This is just the ols formula for beta-hat but I need a symbolic >solution for this special case. > >b = inv(x'x)x'y > >where > >x = 1 t t^2 >1 t t^2 >1 t t^2 > > >and simplify simplify simplify!! > >Thanks, > >Bob If I understand the notation, x is a matrix. Yes? If so, x is singular and doesn't have an inverse. Hence neither does x'x, so the problem has no solution. Or, better put, the problem is ill posed. A dsifferent Bob