Re: Rationalized Fitting
- To: mathgroup at smc.vnet.net
- Subject: [mg125487] Re: Rationalized Fitting
- From: Ray Koopman <koopman at sfu.ca>
- Date: Thu, 15 Mar 2012 00:32:43 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jhienb$b3o$1@smc.vnet.net> <jjmuv3$cen$1@smc.vnet.net> <jjpb32$p6b$1@smc.vnet.net>
On Mar 13, 10:41 pm, Ray Koopman <koop... at sfu.ca> wrote: > First, the data you generate has multiplicative error, > so you should specify Weights->(1/#&) in NonlinearModelFit. With multiplicative error, the error variance is proportional to the square of the expected value, so the weight function should be (#^-2&), because the weights should be inversely proportional to the error variance.