Displaying 20 results from an estimated 20000 matches similar to: "Calculation of r.squared for linear model with offset"
2006 Aug 25
1
R.squared in Weighted Least Square using the Lm Function
Hello all,
I am using the function lm to do my weighted least
square regression.
model<-lm(Y~X1+X2, weight=w)
What I am confused is the r.squared.
It does not seem that the r.squared for the weighted
case is an ordinary 1-RSS/TSS.
What is that precisely?
Is the r.squared measure comparable to that obtained
by the ordinary least square?
<I also notice that
model$res is the unweighted
2012 Jun 04
2
Non-linear curve fitting (nls): starting point and quality of fit
Hi all,
Like a lot of people I noticed that I get different results when I use nls
in R compared to the exponential fit in excel. A bit annoying because often
the R^2 is higher in excel but when I'm reading the different topics on this
forum I kind of understand that using R is better than excel?
(I don't really understand how the difference occurs, but I understand that
there is a
2009 Apr 02
1
calculating drop1 R^2s
This is probably simple, but I just can't see it...
I want to calculate the R^2s for a series of linear models where each
term is dropped in turn. I can get the
RSS from drop1(), and the r.squared from summary() for a given model,
but don't know how to use the
result of drop1() to get the r.squared for each model with one term dropped.
Working example:
library(vcd) # for
2009 Apr 20
1
R-Squared with biglm?
I've been working with a rather large data set (~10M rows), and while biglm works beautifully for generating coefficients, it does not report an r-squared. It does report RSS. Any idea on how one could coax an R-squared out of biglm?
Thanks in advance for any help with this!
Bryan Lim
Lecturer
Department of Finance
University of Melbourne
[[alternative HTML version deleted]]
2005 Sep 13
2
Translating lme model call to lme4
I would appreciate help translating the following lme model to an lmer
function.
lme(lognrms ~ Group*Rotation*muscle*side*support*arms,
random=~1|Subject/Stratum2/rep, data=Data)
Many thanks
Ross Darnell
r.darnell at uq.edu.au
2007 Oct 17
2
Need help with function that includes 2 summation
I am relatively new to R, so this may be a much simpler question than it
seems to me. I am trying to create a function that includes two
summations, and can't figure out how. I am attaching the equation as a
pdf file. This function will then be optimized over a chosen range of
values, but right now I just need help with the function. Thank you.
Zack Darnell
Duke University
--
Zack
2003 Nov 04
2
help with nomogram function
I have fitted a logistic regression model
> failed.lr2$call
lrm(formula = failed ~ Age + task2 + Age:task2, data = time.long,
na.action = na.omit)
using the Design package functions and would like to generate a
nomogram from this model.
the datadist information is generated and stored in
> ddist
time.long$Age time.long$task2
Low:effect 45
2002 Dec 05
2
Problems with segments and multiple graphs
I would like to create a page of two graphs (2 rows by 1 col) and then
draw vertical lines (segments?) on both graphs from the minimum
values to the corresponding maximum value.
So I have tried
#
> y <- rnorm(3000)
> par(mfrow=c(2,1))
> plot(y,type="l")
> plot(cumsum(y),type="l")
> segments(1000,min(cumsum(y)),1000,max(cumsum(y)))
> par(mfg=c(1,1))
>
2002 Feb 15
2
Reordering factor levels
I would like to define the order of the levels of a factor.
The relevel function would work but since I have 20 levels I would prefer
to declare the order explicitly. Using a smaller example
levels(oldfactor)
"b1" "b2" "r1" "r2"
nufactor <- order(oldfactor,order=c("b1","r1","b2","r2")) # my fabricated function
2005 Apr 13
3
A suggestion for predict function(s)
Maybe a useful addition to the predict functions would be to return the
values of the predictor variables. It just (unless there are problems)
requires an extra line. I have inserted an example below.
"predict.glm" <-
function (object, newdata = NULL, type = c("link", "response",
"terms"), se.fit = FALSE,
1999 May 19
1
shell command
Using R (version 0.63.3) for MS windows, I try the following command
> shell(paste("cd ",getenv("RHOME"),sep=""))
which replies with an error message
Too many parameters - FILES\RW0633
which appears to suggest that the space if the path name is causing
difficulties to the cd command. getenv returns
> getenv("RHOME")
RHOME
2007 Mar 13
3
inconsistent behaviour of add1 and drop1 with a weighted linear model
Dear R Help,
I have noticed some inconsistent behaviour of add1 and drop1 with a
weighted linear model, which affects the interpretation of the results.
I have these data to fit with a linear model, I want to weight them by
the relative size of the geographical areas they represent.
_________________________________________________________________________________________
> example
2003 Dec 20
3
Level(3) SIP termination services
John,
I spoke with Level(3) last week regarding SIP termination. They
quoted $0.01/minute, with an 11 Million Minute / Month minimum.
Ugh!
-dg
--------------------------------------------------------------
Darnell Gadberry
President
binaryMedia
darnell AT binmedia DOT com
------------
Date: Fri, 19 Dec 2003 21:12:22 -0500
To: asterisk-users@lists.digium.com
From: John Todd
2006 Nov 21
1
R-squared with and without constant
Greetings Listers!
the R-squared value reported by summary of lm is calculated as
1 - RSS/RSS_m
where RSS_m is the residual sum of squares of a minimal model. In
most cases, the minimal model is simply y = mean(y), but when a
constant is left out of the model, the minimal model is y = 0.
However, if you manually add a constant, R still considers y = 0 the
minimal model. This also causes
2004 Jun 01
1
WinMenu's question
I am using the Windows menu functions below which will work on the
first pass, but if I repeat the same script I cannot get the
WinMenuAddItem to work. This is a problem if I change the menu
structure and reread the source code I am forced to quit and restart Rgui.
"try.menu" <- function(){
OS <- .Platform$OS.type
GUI <- .Platform$GUI
if (!(OS == "windows" &
2010 Jun 11
3
Calculation of r squared from a linear regression
Hi,
I'm trying to verify the calculation of coefficient of determination (r squared) for linear regression. I've done the calculation manually with a simple test case and using the definition of r squared outlined in summary(lm) help. There seems to be a discrepancy between the what R produced and the manual calculation. Does anyone know why this is so? What does the multiple r squared
2007 Apr 18
1
[Bridge] RE: [VLAN] Re: [PATCH/RFC] Let {ip, arp}tables "see" bridged VLAN tagged{I,AR}P packets
-----Original Message-----
>From: Tommy Christensen [mailto:tommy.christensen@tpack.net]
>Sent: Wednesday, October 08, 2003 10:09 AM
>To: Christian Darnell
>Cc: 'Linux 802.1Q VLAN'; Bart De Schuymer; netdev@oss.sgi.com; bridge
>Subject: Re: [Bridge] RE: [VLAN] Re: [PATCH/RFC] Let {ip, arp}tables
>"see" bridged VLAN tagged{I,AR}P packets
>
>
>
>This
2013 Jan 20
3
strucchange breakpoints r-squared
Can anyone please tell me how to get the r-squared output from a piecewise
(segmented) regression using the strucchange package? Here is the R code I
have tried thus far.
library(lmtest)
library(strucchange)
data <- ts(c(rnorm(30), runif(30)), frequency = 12, start = c(2005, 01))
bpts <- breakpoints(data ~ 1)
print(bpts)
summary(bpts)
coeftest(bpts)
[[alternative HTML version
2006 Jan 10
2
Obtaining the adjusted r-square given the regression coefficients
Hi people,
I want to obtain the adjusted r-square given a set of coefficients (without the intercept), and I don't know if there is a function that does it. Exist????????????????
I know that if you make a linear regression, you enter the dataset and have in "summary" the adjusted r-square. But this is calculated using the coefficients that R obtained,and I want other coefficients
2007 Jan 25
3
Error in loadNamespace(name) (PR#9464)
Full_Name: Ross Darnell
Version: 2.4.1
OS: Linux
Submission from: (NULL) (130.102.133.33)
rdarnell at pc:~/Data$ ls -al .RData
-rwxrwxrwx 2 root root 13551 2006-12-06 08:58 .RData
rdarnell at pc:~/Data$ R
R version 2.4.1 (2006-12-18)
Copyright (C) 2006 The R Foundation for Statistical Computing
ISBN 3-900051-07-0
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to