Displaying 20 results from an estimated 300 matches similar to: ""gam()" in "gam" package"
2007 Dec 18
1
R-users
R-users
E-mail: r-help@r-project.org
I have a quenstion on "gam()" in "gam" package.
The help of gam() says:
'gam' uses the _backfitting
algorithm_ to combine different smoothing or fitting methods.
On the other hand, lm.wfit(), which is a routine of gam.fit() contains:
z <- .Fortran("dqrls", qr = x * wts, n = n, p = p, y = y *
2008 Oct 19
2
definition of "dffits"
R-users
E-mail: r-help@r-project.org
Hi! R-users.
I am just wondering what the definition of "dffits" in R language is.
Let me show you an simple example.
function() {
library(MASS)
xx <- c(1,2,3,4,5)
yy <- c(1,3,4,2,4)
data1 <- data.frame(x=xx, y=yy)
lm.out <- lm(y~., data=data1, x=T)
lev1 <- lm.influence(lm.out)$hat
sig1 <-
2002 Sep 30
2
"Rcmd SHLIB" does not work
R-users
E-mail: r-help at stat.math.ethz.ch
Hi!
I would like to produce DLL files to be linked to
R objects on Windows98SE. The source files are
written in Fortran77.
I input the command below on R console.
Rcmd SHLIB aaa.f
The result is:
Error: syntax error
Does this mean that "Rcmd SHLIB aaa.f" contains
symtax error, or "aaa.f" contains it?
Or do I need to do
2008 Sep 16
1
1-SE rule in mvpart
Hello,
I'm using mvpart option xv="1se" to compute a regression tree of good size
with the 1-SE rule.
To better understand 1-SE rule, I took a look on its coding in mvpart, which
is :
Let z be a rpart object ,
xerror <- z$cptable[, 4]
xstd <- z$cptable[, 5]
splt <- min(seq(along = xerror)[xerror <= min(xerror) + xvse * xstd])
I interprete this as following: the
2007 Dec 26
1
Cubic splines in package "mgcv"
R-users
E-mail: r-help@r-project.org
My understanding is that package "mgcv" is based on
"Generalized Additive Models: An Introduction with R (by Simon N. Wood)".
On the page 126 of this book, eq(3.4) looks a quartic equation with respect
to
"x", not a cubic equation. I am wondering if all routines which uses
cubic splines in mgcv are based on this quartic
2012 Jul 06
1
Definition of AIC (Akaike information criterion) for normal error models
Dear R users (r-help@r-project.org),
The definition of AIC (Akaike information criterion)
for normal error models has just been changed.
Please refer to the paper below on this matter. Eq.(22) is
the new definition. The essential part is RSS(n+q+1)/(n-q-3);
it is close to GCV. The paper is temporarily available at
the "Papers In Press" place.
Kunio Takezawa(2012): A Revision of
2002 Oct 02
0
Re: Rcmd SHLIB" does not work
R users
E-mail: r-help at stat.math.ethz.ch
I really appreciate information from Dr. Ligges and Dr. Wang.
I managed to create DLL files by MinGW and use them as subroutines
on R.
Thank you very much again.
******** E-mail: takezawa at affrc.go.jp ********
***** http://cse.naro.affrc.go.jp/takezawa/patent-e.html *****
2008 Oct 01
0
xpred.rpart() in library(mvpart)
R-users
E-mail: r-help@r-project.org
Hi! R-users.
http://finzi.psych.upenn.edu/R/library/mvpart/html/xpred.rpart.html
says:
data(car.test.frame)
fit <- rpart(Mileage ~ Weight, car.test.frame)
xmat <- xpred.rpart(fit)
xerr <- (xmat - car.test.frame$Mileage)^2
apply(xerr, 2, sum) # cross-validated error estimate
# approx same result as rel. error from printcp(fit)
apply(xerr, 2,
2006 Feb 01
1
Off topic: nonparametric regression
Hi All,
What do you consider to be the best book(reference) on nonparametric regression?
I am currently reading the book of Kunio Takezawa(2006): "Introduction to nonparametric regression".
Is the book of Hardle(1990): "Applied nonparametric regression" better? or maybe another book?
This is off topic, but most of the books is using R or S-plus.
Thanks
Hennie
2011 Aug 16
0
Cubic splines in package "mgcv"
re: Cubic splines in package "mgcv"
I don't have access to Gu (2002) but clearly the function R(x,z) defined
on p126 of Simon Wood's book is piecewise quartic, not piecewise cubic.
Like Kunio Takezawa (below) I was puzzled by the word "cubic" on p126.
As Simon Wood writes, this basis is not actually used by mgcv when
specifying bs="cr".
Maybe the point is
2004 Oct 28
2
Weighted regresion using lm
Hi:
Could anyone help me to clarify this: are the weights normalized inside lm
function (package:stats) before applied to the error term? For example:
>lm (cost ~ material, weights=quatity, data=receipt)
will lm normalize quatity such that sum(quatity) = 1? I traced to lm.wfit and
then the weights get transferred into a precompiled FORTRAN module so I can't
figure out. Thanks!
2005 Mar 24
1
Robust multivariate regression with rlm
Dear Group,
I am having trouble with using rlm on multivariate data sets. When I
call rlm I get
Error in lm.wfit(x, y, w, method = "qr") :
incompatible dimensions
lm on the same data sets seem to work well (see code example). Am I
doing something wrong?
I have already browsed through the forums and google but could not find
any related discussions.
I use Windows XP and R
2008 May 07
2
Estimating QAIC using glm with the quasibinomial family
Hello R-list. I am a "long time listener - first time caller" who has
been using R in research and graduate teaching for over 5 years. I
hope that my question is simple but not too foolish. I've looked
through the FAQ and searched the R site mail list with some close hits
but no direct answers, so...
I would like to estimate QAIC (and QAICc) for a glm fit using the
2008 Aug 07
1
Fitted values with small weights in lm.wfit (PR#11979)
Full_Name: Alexander Blocker
Version: 2.7.1
OS: Ubuntu 8.04 / Windows XP
Submission from: (NULL) (76.119.235.225)
When running lm(modeleq, weights=wt, data=dataset) with small weights (<1e-10),
I have encountered an odd phenomenon with fitted values. Due to numerical
precision issues, the fitted values and residuals returned by lm.wfit (from its
.Fortran call to dqrls) can differ greatly from
2013 Oct 17
1
pamer.fnc y la nueva versión de R
Hola buenas noches,
tengo un problema bastante gordo. ¿A alguno le ha dejado de funcionar las
funciones pamer.fnc y mcp.fnc con la nueva versión de R? La semana pasada
formatee el ordenador y ahora scripts antiguos no funcionan. La cuestión es
que me precupa que no funcione el ejemplo de tutorial del autor.
Os dejo un script que debería de funcionar y no lo hace
2004 Aug 06
2
gam --- a new contributed package
I have contributed a "gam" library to CRAN,
which implements "Generalized Additive Models".
This implementation follows closely the description in
the GAM chapter 7 of the "white" book "Statistical Models in S"
(Chambers & Hastie (eds), 1992, Wadsworth), as well as the philosophy
in "Generalized Additive Models" (Hastie & Tibshirani 1990,
2004 Aug 06
2
gam --- a new contributed package
I have contributed a "gam" library to CRAN,
which implements "Generalized Additive Models".
This implementation follows closely the description in
the GAM chapter 7 of the "white" book "Statistical Models in S"
(Chambers & Hastie (eds), 1992, Wadsworth), as well as the philosophy
in "Generalized Additive Models" (Hastie & Tibshirani 1990,
2002 Jun 26
3
Bug or failing understanding?
Hola!
I seem to remember i used to have the same name of argument and default
value in argument list to functions, but (rw1.5.1) this seems not to
work:
> x <- 3
> test <- function(x=x) x*x
> test(7)
[1] 49
> test()
Error in test() : recursive default argument reference
here is a code fragment from lm() using the same syntax:
else {
x <- model.matrix(mt, mf,
2007 Oct 12
3
no visible binding
Could someone advise me about how to react to the message:
* checking R code for possible problems ... NOTE
slm: no visible binding for global variable 'response'
from R CMD check SparseM with
* using R version 2.6.0 Under development (unstable) (2007-09-03 r42749)
The offending code looks like this:
"slm" <-
function (formula, data, weights, na.action, method =
2010 May 26
2
Survival analysis extrapolation
Dear all,
I'm trying to fit a curve to some 1 year failure-time data, so that I can
extrapolate and predict failure rates up to 3 years. The data is in the
general form:
Treatment Time Status
Treatment A 28 0
Treatment B 28 0
Treatment B 28 0
Treatment A 28