Displaying 20 results from an estimated 500 matches similar to: "Mallows' distance or Earth Mover's distance in R?"
2008 Oct 22
1
forward stepwise regression using Mallows Cp
So I recognize that:
1. many people hate forward stepwise regression (i've read the archives)--but I need it
2. step() or stepAIC are two ways to get a stepwise regression in R
But here's the thing: I can't seem to figure out how to specify that I want the criteria to be Mallow's Cp (and then to subsequently tell me what the Cp stat is). I know it has something to do with
2009 Jun 24
1
how to undo automatic loading of packages?
I wanted to try out package distrMod, so I did
> install.packages('distrMod')
> library(distrMod)
and played around, saved and quit.
Now whenever I start up in this directory, I get distr and lots of other
stuff loaded and lots of messages.
How do I keep it from automatically loading, other than starting over in
another directory?
I read ?Startup, but I couldn't suss out
2004 Dec 16
3
3 questions
Hello R users,
I have three questions and I would be grateful if someone could give me an answer to each of these.
1) I have constracted a function that returns an output, which runs in a while( condition ){ run function } loop. I would like to know if there is a way to get the outputs in different windows, every time the function runs, so as to compare easier the results.
2) In my
2003 Nov 23
2
where to get the "leaps" package
Dear all
I am supposed to use Mallow's Cp creterion to select a model which require
a "leaps" package. the version right now I am using is R
1.7.1(os:windows), the "leaps" package is not included. please let me know
how and where
can I get this package and add it to the current version, any caution on
adding this package is highly appreciated.
thank you
best
2009 Dec 09
2
Recent TeX changes and R/package manuals
As some of you will be aware, TeXLive 2009 was released last month
having blocked updates on earlier versions since May. This has lead
to a flood of updates of LaTeX packages, as a result of which the
PDF manuals of R 2.10.0 and earlier will no longer build, for two
separate reasons.
For MiKTeX users: at least version 2.8 (the current one) has the same
updates (a week or so later) and has
2005 Feb 24
2
Forward Stepwise regression based on partial F test
I am hoping to get some advise on the following:
I am looking for an automatic variable selection procedure to reduce the
number of potential predictor variables (~ 50) in a multiple regression
model.
I would be interested to use the forward stepwise regression using the
partial F test.
I have looked into possible R-functions but could not find this
particular approach.
There is a function
2011 Mar 18
3
exploring dist()
Hello, everybody,
I hope somebody could help me with a dist() function.
I have a data frame of size 2*4087 (col*row), where col corresponds to the
treatment and rows are
species, values are Hellinger distances, I should reconstruct a distance
matrix
with a dist() function. I know that "euclidean" method should be used.
When I type:
dist(dframe,"euclidean")
it gives me a
2005 May 11
2
Regsubsets()
Dear List members
I am using the regsubsets function to select a few predictor variables
using Mallow's Cp:
> sel.proc.regsub.full <- regsubsets(CO2 ~ v + log(v) + v.max + sd.v +
tad + no.stops.km + av.stop.T + a + sd.a + a.max + d + sd.d + d.max +
RPA + P + perc.stop.T + perc.a.T + perc.d.T + RPS + RPSS + sd.P.acc +
P.dec + da.acc.1 + RMSACC + RDI + RPSI + P.acc + cov.v + cov.a +
2009 Oct 02
1
decision trees using the Hellinger distance rather than
Hi, while working with decision trees and unbalanced data, I came across the
use of the Hellinger distance as an alternative to information gain [1,2],
when dealing with skewed data. Does anybody know of R implementations of
this approach to decision trees?
Thanks,
[1] http://www.cse.nd.edu/Reports/2008/TR-2008-06.pdf
[2] http://csmr.ca.sandia.gov/~wpk/slides/wdmda-sem.pdf
--
Rajarshi Guha
NIH
2009 Jun 23
1
implementing Maximum Likelihood with distrMod when only the PDF is known
Dear R users and Dear authors of the distr package and sequels
I am trying to use the (very nice) package distrMod as I want to
implement maximum likelihood (ML) fit of some univariate data for which
I have derived a theoretical continuous density (pdf). As it is a
parametric density, I guess that I should implement myself a new
distribution of class AbscontDistributions (as stated in the pdf
2017 Sep 16
2
Help with RDA analysis, function ''varpart'' in vegan
I'm trying to perform a RDA analysis in the vegan package using the
"varpart" function.
I have a matrix of community structure data in different sites (rows),
which I want to explain using 3 matrices of environmental data. The 3
matrices are:
water quality parameters;
local land use variables;
total land use variables.
In each matrix, the number of the rows is the same (the
2009 Jan 18
1
regression model selection
Hello,
Newbie here, be gentle ;)
I have a reference book that discusses regression model selection using
several methods - what they call 'Forward Model Selection' i.e. add one
variable at a time and examining R, R^2, Mallow's C-p value, etc., 'Backward
Model Selection' i.e. starting out with all the variables included and then
remove them one at a time, and examining for
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
[[alternative HTML version deleted]]
2007 Sep 17
1
Stepwise logistic model selection using Cp and BIC criteria
Hi,
Is there any package for logistic model selection using BIC and Mallow's Cp
statistic? If not, then kindly suggest me some ways to deal with these
problems.
Thanks.
--
View this message in context: http://www.nabble.com/Stepwise-logistic-model-selection-using-Cp-and-BIC-criteria-tf4464430.html#a12729613
Sent from the R help mailing list archive at Nabble.com.
2005 Mar 02
1
Leaps & regsubsets
Hello
I am trying to use all subsets regression on a test dataset consisting
of 11 trails and 46 potential predictor variables.
I would like to use Mallow's Cp as a selection criterion.
The leaps function would provide the required output but does not work
with this many variables (see below).
The alternative function regsubsets should be used, but I am not able to
define the function in
2023 Dec 08
2
regarding CCA plot
Hii rstudio members
I am learning rstudio, For my manuscript I am trying to plot CCA using
species and environmental data. But I am getting error like
Error in cca.default(sptrans, envtrans) :
all row sums must be >0 in the community data matrix
*My code is like *
library(vegan)
library(ggplot2)
library(dplyr)
rassspec<-read.csv("C:/Users/hp/Desktop/R_data/rassspec.csv",
2017 Sep 17
0
Help with RDA analysis, function ''varpart'' in vegan
I am not familiar with the vegan package, so I am just making a guess here.
If 'na.action=na.omit' is part of the call to varpart, try removing it from
the function call and moving it above as follows:
options(na.action="na.omit")
RDA_Ger <- varpart(comm, x1, x2, x3, transfo="hellinger", scale = FALSE)
Maybe that will help.
Regards,
Eric
On Sat, Sep 16, 2017 at
2007 Feb 27
2
RDA and trend surface regression
Dear all,
I'm performing RDA on plant presence/absence data, constrained by
geographical locations. I'd like to constrain the RDA by the "extended
matrix of geographical coordinates" -ie the matrix of geographical
coordinates completed by adding all terms of a cubic trend surface
regression- .
This is the command I use (package vegan):
>rda(Helling ~
2010 Aug 25
1
Documenting S4 Methods
I'm in the process of converting some S3 methods to S4 methods.
I have this function :
setGeneric("enrichmentCalc", function(rs, organism, seqLen, ...){standardGeneric("enrichmentCalc")})
setMethod("enrichmentCalc", c("GenomeDataList", "BSgenome"), function(rs, organism, seqLen, ...) {
... ... ...
})
2008 Jan 09
3
likelihood from test result
Is there any automatic mechanism for extracting a likelihood or test
statistic distribution (PDF or CDF) from an object of class "htest" or
from another object of a general class encoding a hypothesis test
result?
I would like to have a function that takes "x", an object of class
"htest", as its only argument and that returns the likelihood or test
statistic