Displaying 20 results from an estimated 10000 matches similar to: "has anyone implemented LARS with the "positive lasso"?"
2006 Sep 15
2
LARS for generalized linear models
Hi,
Is there an R implementation of least angle regression for binary response
modeling? I know that this question has been asked before, and I am also
aware of the "lasso2" package, but that only implements an L1 penalty, i.e.
the Lasso approach.
Madigan and Ridgeway in their discussion of Efron et al (2004) describe a
LARS-type algorithm for generalized linear models. Has
2010 Dec 06
2
How to get lasso fit coefficient(given penalty tuning parameter \lambda) using lars package
Hi, all,
I am using the lars package for lasso estimate. So I get a lasso
fit first:
lassofit = lars(x,y,type ="lasso",normalize=T, intercept=T)
Then I want to get coefficient with respect to a certain value of \lambda
(the tuning parameter), I know lars has three mode options c("step",
"fraction", "norm"), but can I use the \lambda value instead
2003 Jun 13
1
lars - lasso problem
hello
I tried to use lars() but neither with my own data nor with the sample data it
works. I get in both cases the following error prompt:
> data(diabetes)
> par(mfrow=c(2,2))
> attach(diabetes)
> x<-lars(x,y)
Error in one %*% x : requires numeric matrix/vector arguments
> x<-lars(x,y, type="lasso")
Error in one %*% x : requires numeric matrix/vector arguments
2005 May 31
3
lars / lasso with glm
We have been using Least Angle Regression (lars) to help identify
predictors in models where the outcome is continuous. To do so we have
been relying on the lars package. Theoretically, it should be possible
to use the lars procedure within a general linear model (glm) framework
- we are particular interested in a logistic regression model. Does
anyone have examples of using lars with logistic
2007 Aug 02
2
lasso/lars error
I'm having the exact problem outlined in a previous post from 2005 -
unfortunately the post was never answered:
http://tolstoy.newcastle.edu.au/R/help/05/10/15055.html
When running:
lm2=lars(x2,y,type="lasso",use.Gram=F)
I get an error:
Error in if (zmin < gamhat) { : missing value where TRUE/FALSE needed
...when running lasso via lars() on a 67x3795 set of predictors. I
2009 Oct 27
1
lasso plot using LARS
When plotting a lars object, I cannot find a way to plot solid lines.
Even when the arguments breaks=F and lty="solid" are used, the vertical
lines at the break points do not plot but asterisks indicating the
breaks still plot as part of each path leaving solid lines broken up by
asterisks at the break points. I'm using the following code.
larsfit <-
2012 Jul 12
1
lars package to do lasso
Dear all
I am using lars package to do lasso in R. I dont undesrtand what max.steps do?and how I can understand from the outputs to obtain the last steps in this packagethanks for your helpbest
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2004 Oct 28
1
qustion with lars (lasso) package
Dear All,
I am using lars package written by Dr. Trevor Hastie, the version is lars_0.9-5 downloaded from cran. When I ran the diabetes example data attached in package, I found that the beta outputs from different machines are different. The difference is only about 10^-11 to 10^-12, some friends suggested that it possibly is a machine precision problem. But I check the machine numerical
2006 Sep 18
0
Propensity score modeling using machine learning methods. WAS: RE: LARS for generalized linear models
There may be benefits to having a machine learning method that
explicitly targets covariate balance. We have experimented with
optimizing the weights directly to obtain the best covariate balance,
but got some strange solutions for simple cases that made us wary of
such methods.
Machine learning methods that yield calibrated probability estimates
should do well (e.g. those that optimize the
2006 Mar 06
0
Problems with R CMD Rdconv and R CMD Sd2Rd (PR#8661)
I'm using R 2.2.0 on Windows.
Doing some conversions of help files. Internal comments indicate
that the Sd2Rd conversion is "Converted by Sd2Rd version 1.21."
I'm converting
.d -> .Rd
.sgml -> .Rd
using Sd2Rd, then checking by using Rdconv to
convert .Rd back to .d or .sgml.
Here are errors in some of the conversions.
The most significant errors are in .Rd to .sgml.
2011 May 24
1
anyone using LARS package in R
Hi useR's,
Has anyone used the "Lars" package in R before? If so, is there any tutorial
(not manual) or worked out example online for this R package that one can go
through to figure out how one can use this package with lasso regression?
I appreciate any help I can get in this direction.
Sincerely,
Vishal
--
*Vishal Thapar, Ph.D.*
*Scientific informatics Analyst
Cold Spring
2003 Apr 30
0
Least Angle Regression packages for R
Least Angle Regression software: LARS
"Least Angle Regression" ("LAR") is a new model selection
algorithm; a useful and less greedy version of traditional
forward selection methods. LAR is described in detail in a paper
by Brad Efron, Trevor Hastie, Iain Johnstone and Rob Tibshirani,
soon to appear in the Annals of Statistics.
The paper, as well as R and Splus packages, are
2003 Apr 30
0
Least Angle Regression packages for R
Least Angle Regression software: LARS
"Least Angle Regression" ("LAR") is a new model selection
algorithm; a useful and less greedy version of traditional
forward selection methods. LAR is described in detail in a paper
by Brad Efron, Trevor Hastie, Iain Johnstone and Rob Tibshirani,
soon to appear in the Annals of Statistics.
The paper, as well as R and Splus packages, are
2012 Jun 16
0
Selecting correlated predictors with LASSO
I'm using the package 'lars' in R with the following code:
> library(lars)
> set.seed(3)
> n <- 1000
> x1 <- rnorm(n)
> x2 <- x1+rnorm(n)*0.5
> x3 <- rnorm(n)
> x4 <- rnorm(n)
> x5 <- rexp(n)
> y <- 5*x1 + 4*x2 + 2*x3 + 7*x4 + rnorm(n)
> x <- cbind(x1,x2,x3,x4,x5)
> cor(cbind(y,x))
y x1 x2
2007 Jun 12
1
LASSO coefficients for a specific s
Hello,
I have a question about the lars package. I am using this package to get the coefficients at a specific LASSO parameter s.
data(diabetes)
attach(diabetes)
object <- lars(x,y,type="lasso")
cvres<-cv.lars(x,y,K=10,fraction = seq(from = 0, to = 1, length = 100))
fits <- predict.lars(object, type="coefficients", s=0.1, mode="fraction")
Can I assign
2011 Jun 06
1
Lasso for k-subset regression
Dear R-users
I'm trying to use lasso in lars package for subset regression, I have a
large matrix of size 1000x100 and my aim is to select a subset k of the 100
variables.
Is there any way in lars to fix the number k (i.e. to select the best 10
variables)
library(lars)
aa=lars(X,Y,type="lasso",max.steps=200)
plot(aa,plottype="Cp")
aa$RSS
which.min(aa$RSS)
2011 May 24
1
seeking help on using LARS package
Hi,
I am writing to seek some guidance regarding using Lasso regression with the
R package LARS. I have introductory statistics background but I am trying to
learn more. Right now I am trying to duplicate the results in a paper for
shRNA prediction "An accurate and interpretable model for siRNA efficacy
prediction, Jean-Philippe Vert et. al, Bioinformatics" for a Bioinformatics
project
2009 Jul 12
0
Plotting problem [lars()/elasticnet()]
Dear all,
I am using modified LARS algorithm (ref: The Adaptive Lasso and Its Oracle
Properties, Zou 2006) for adaptive lasso penalized linear regression.
1. w(j) <- |beta_ols(j)|^(-gamma) gamma>0 and j = 1,...,p
2. define x_new(j) <- x(j)*w(j)
3. apply LARS to solve modified lasso problem
out.adalasso <- lars(X_new,y,type="lasso") or enet(X_new,
2007 Mar 15
1
Model selection in LASSO (cross-validation)
Hi, I know how to use LASSO for model selection based on the Cp criterion.
I heard that we can also use cross validation as a criterion too. I used
cv.lars to give me the lowest predicted error & fraction. But I'm short of
a step to arrive at the number of variables to be included in the final
model. How do we do that? Is it the predict.lars function? i tried >
2009 Dec 16
0
lasso regression coefficients
Dear list,
I have been trying to apply a simple lasso regression on a 10-element
vector, just to see how this method works so as to later implement it on
larger datasets. I thus create an input vector x:
* x=rnorm(10)*
I add some noise
* noise=runif(n=10, min=-0.1, max=0.1)*
and I create a simple linear model which calculates my output vector y
* y=2*x+1+noise*
I then do