[R] Linear Regression with Constraints

Hi! I am a bit new to R. I am looking for the right function to use for a multiple regression problem of the form: y = c1 + x1 + (c2 * x2) - (c3 * x3) Where c1, c2, and c3 are the desired regression coefficients that are subject to the following constraints: 0.0 < c2 < 1.0, and 0.0 < c3 < 1.0 y

[R] Trouble with optim on a specific problem

Hello! I am getting the following errors when running optim() [I tried optim() with 3 different methods as you can see]: Error in optim(c(0.66, 0.999, 0.064), pe, NULL, method = "L-BFGS-B") : objective function in optim evaluates to length 6 not 1 > out <- optim( c(0.66, 0.999, 0.064),

Re: [R] Trouble with optim on a specific problem

319, 0.087378640776699, 0.549295774647887, 0.0596026490066225, 0.61578947368421) Thank you again, Stu > -Original Message- > From: Liviu Andronic [mailto:landronim...@gmail.com] > Sent: Tuesday, June 16, 2009 2:35 AM > To: Stu @ AGS > Cc: r-help@r-project.org > Subject: Re: [R]

[R] The most straightfoward way to write a function that sums over the rows of a matrix

Hello! I am trying to write a function with vector and data.frame parameters that uses the sum() function and values from the rows of the data.frame. I need to pass this function as a parameter to optim(). My starting point is: observs <- data.frame(y, x1, x2, x3) Fn <- function(par,

Re: [R] Trouble with optim on a specific problem

pecific problem > > Hello, > > On 6/16/09, Stu @ AGS wrote: > > Thanks for your response! > > No, my basic equation does not use matrices at all. It takes scalar > values and returns a scalar. > > > Not quite. Taking the example above, if you run the f

[R] The R-Inferno

et.com] > Sent: Tuesday, June 16, 2009 11:31 AM > To: Stu @ AGS > Subject: Re: [R] The most straightfoward way to write a function that > sums over the rows of a matrix > > 'The R Inferno' may be of use to you. > > > > Patrick Burns > patr...@burns-

[R] ui and ci explanatory documentation

Hi Livia and everyone, Did you ever get a response on this question from last year (Jan 2008)? I am also looking for more explanatory documentation on the ui and ci parameters for the function constrOptim(). The examples provided in the R help and the full refe

[R] Constrained Optimization, a full example

After a few days of work, I think I nearly have it. Unfortunately, theta is unchanged after I run this (as a script from a file). I thought that theta would contain the fitted parameters. The goal here is to find the least squares fit according to the function defined as "rss" subject to the

[R] Specifying ui and ci such that ui %*% theta - ci >= 0

Hi, I am a bit stuck on specifying ui and ci. I have read Lange's book ((1999) Numerical Analysis for Statisticians) to his approach and unfortunately his descriptions were not helpful for me. Here is what I have: ui <- rbind(c(0, -1, 0), c(0, 0, -1)) ci <- c(0, -1, -1))

[R] Curve fit a nonlinear equation with box constraints: success, many thanks!

Dear R Helper Community! Thank you for all your help and suggestions. For your reference and any future person searching the archives, here is the solution that did what I wanted it to do. As background, my goal was to find the coefficients for the following equation form: y ~ c1 * x1 *