Displaying 20 results from an estimated 10000 matches similar to: "Question on partial effect"
2008 Nov 20
1
gam and ordination (vegan and labdsv surf and ordisurf)
I have a general question about using thin plate splines in the surf
and ordisurf routines. My rudimentary knowledge of a gam is that with
each predictive variable there is a different smooth for each one and
then they are added together with no real interaction term (because
they don't handle this well?). Now, If I have two variables that
have a high D^2 score and a low GCV score (I am
2008 Jan 15
1
covariate in a glm
Hello mailing list!
I would like to know, how I can introduce a covariate in a glm, I've two factors and a covariate.
Thank you very much!
_______________________________________________________________________________________________
Michelangelo La Spina
Equipo de Protección de cultivos - Control Biológico
Departamento de Biotecnología y Protección de Cultivos
Instituto Murciano de
2009 Jul 08
1
Comparing GAMMs
Greetings!
I am looking for advice regarding the best way to compare GAMMs. I
know other model outputs return enough information for R's AIC, ANOVA,
etc. commands to function, but this is not the case with GAMM unless one
specifies the gam or lme portion. I know these parts of the gamm contain
items that will facilitate comparisons between gamms. Is it correct to
simply use these values
2004 Nov 04
3
sub- and superscript in plot labels
Dear List,
I need to add a subscript and a superscript to some of the ions in the
labels on some plots.
I have got to here but now I'm stuck:
plot(1:10, xlab = expression(paste("nm SO"[4], " ", mu, "eq cm"^{-2}, "
yr"^{-1})))
Which gives almost what I require. No matter what I tried, however, I
could not get bot a sub script *and* a superscript
2013 Nov 25
4
lmer specification for random effects: contradictory reults
Hi All,
I was wondering if someone could help me to solve this issue with lmer.
In order to understand the best mixed effects model to fit my data, I
compared the following options according to the procedures specified in many
papers (i.e. Baayen
<http://www.google.it/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDsQFjAA
2010 Jan 28
2
Data.frame manipulation
Hi All,
I'm conducting a meta-analysis and have taken a data.frame with multiple
rows per
study (for each effect size) and performed a weighted average of effect size
for
each study. This results in a reduced # of rows. I am particularly
interested in
simply reducing the additional variables in the data.frame to the first row
of the
corresponding id variable. For example:
2011 Apr 08
1
Variance of random effects: survreg()
I have the following questions about the variance of the random effects in the survreg() function in the survival package:
1) How can I extract the variance of the random effects after fitting a model?
For example:
set.seed(1007)
x <- runif(100)
m <- rnorm(10, mean = 1, sd =2)
mu <- rep(m, rep(10,10))
test1 <- data.frame(Time = qsurvreg(x, mean = mu, scale= 0.5, distribution =
2005 Aug 16
2
problem using model.frame()
Hi I'm having a problem with model.frame, encapsulated in this example:
y1 <- matrix(c(3,1,0,1,0,1,1,0,0,0,1,0,0,0,1,1,0,1,1,1),
nrow = 5, byrow = TRUE)
y1 <- as.data.frame(y1)
rownames(y1) <- paste("site", 1:5, sep = "")
colnames(y1) <- paste("spp", 1:4, sep = "")
y1
model.frame(~ y1)
Error in model.frame(formula, rownames,
2005 Nov 03
4
merging dataframes
Dear List,
I often have to merge two or more data frames containing unique row
names but with some columns (names) common to the two data frames and
some columns not common. This toy example will explain the kind of setup
I am talking about:
mat1 <- as.data.frame(matrix(rnorm(20), nrow = 5))
mat2 <- as.data.frame(matrix(rnorm(20), nrow = 4))
rownames(mat1) <- paste("site",
2008 Feb 07
2
How to calculate normality of the residuals from a test in R?
En innebygd og tegnsett-uspesifisert tekst ble skilt ut...
Navn: ikke tilgjengelig
Nettadresse: https://stat.ethz.ch/pipermail/r-help/attachments/20080207/891f1e80/attachment.pl
2005 Aug 03
1
deparse(substitute(x)) and S3 methods
Dear List,
I have the following function:
coca <- function(x, ...)
{
if(is.null(class(x))) class(x) <- data.class(x)
UseMethod("coca", x)
}
and a default method
coca.default <- function(x, y, method = c("predictive", "symmetric"),
reg.method = c("simpls", "eigen"), weights =
NULL,
2005 Aug 02
1
problem using evaluating a formula
##data
y1 <- matrix(c(3,1,0,1,0,1,1,0,0,0,1,0,0,0,1,1,0,1,1,1),
nrow = 5, byrow = TRUE)
y2 <- matrix(c
(3,0,10,3,3,0,0,1,1,0,0,0,0,0,1,0,1,0,0,2,1,0,1,1,0,2,1,1,4,1),
nrow = 5, byrow = TRUE)
y1 <- as.data.frame(y1)
y2 <- as.data.frame(y2)
rownames(y1) <- rownames(y2) <- paste("site", 1:5, sep = "")
colnames(y1) <-
2006 Oct 31
3
one problem about how to hold graphic with R
Sorry to disturb you, but can you help me to solve one little problem?
I want to draw a graphic after another with R
but I cannot find the first one after that.
Do you know the command to hold the graphic with R?
I remember with Matlab you may use "hold on".
Thanks.
--
Baohua Yang
Email:yangbaohua@gmail.com
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2010 Feb 15
2
creating functions question
Hi All,
I am interested in creating a function that will take x number of lm
objects and automate the comparison of each model (using anova). Here
is a simple example (the actual function will involve more than what
Im presenting but is irrelevant for the example):
# sample data:
id<-rep(1:20)
n<-c(10,20,13,22,28,12,12,36,19,12,36,75,33,121,37,14,40,16,14,20)
2005 Apr 06
1
axis.Date problem, bug(?)
Dear List,
I have the following problem with axis.Date, here is an artificial example:
dates <- scan(what = "character")
"25/03/2000" "26/03/2000" "27/03/2000" "28/03/2000" "29/03/2000"
"30/03/2000" "31/03/2000" "01/04/2000" "02/04/2000" "03/04/2000"
"04/04/2000"
2011 Oct 26
2
Error in summary.mlm: formula not subsettable
When I fit a multivariate linear model, and the formula is defined
outside the call to lm(), the method summary.mlm() fails.
This works well:
> y <- matrix(rnorm(20),nrow=10)
> x <- matrix(rnorm(10))
> mod1 <- lm(y~x)
> summary(mod1)
...
But this does not:
> f <- y~x
> mod2 <- lm(f)
> summary(mod2)
Error en object$call$formula[[2L]] <- object$terms[[2L]]
2006 Mar 11
6
is there a formatted output in R?
something like "sprintf" in C?
so I can do:
print(sprintf("the correct result is %3.4f\n", myresult));
-------
Also, I am desperately looking for a "clear console screen" function in
R...
thanks a lot!
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2005 Aug 16
4
as.character and a formula
Dear list,
given this formula:
> fmla <- formula(y1 ~ spp1 + spp2 + spp3 + spp5)
> fmla[[3]]
spp1 + spp2 + spp3 + spp5
is this the intended behaviour of as.character:
> as.character(fmla[[3]])
[1] "+" "spp1 + spp2 + spp3" "spp5"
? Where does the extra "+" come from?
> as.character(fmla)
[1] "~"
2010 Feb 20
3
aggregating using 'with' function
Hi All,
I am interested in aggregating a data frame based on 2
categories--mean effect size (r) for each 'id's' 'mod1'. The
'with' function works well when aggregating on one category (e.g.,
based on 'id' below) but doesnt work if I try 2 categories. How can
this be accomplished?
# sample data
id<-c(1,1,1,rep(4:12))
n<-c(10,20,13,22,28,12,12,36,19,12,
2003 Oct 08
1
plotting results from leaps library
Hi
In trying to fit a linear model , I use the leaps() function to determine wich predictors I should include in my model.
I would like to plot the Mallow's Cp criteria against p with the indexes of selected model variates as points labels
Is there already such a function? (I could not find it)
Thanks
Anne
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