similar to: how to compute condition index?

Displaying 20 results from an estimated 2000 matches similar to: "how to compute condition index?"

2004 Aug 16
2
mutlicollinearity and MM-regression
Dear R users, Usually the variance-inflation factor, which is based on R^2, is used as a measure for multicollinearity. But, in contrast to OLS regression there is no robust R^2 available for MM-regressions in R. Do you know if an equivalent or an alternative nmeasure of multicollinearity is available for MM-regression in R? With best regards, Carsten Colombier Dr. Carsten Colombier Economist
2004 Sep 21
3
how to take this experiment with R?
How about: x <- data.frame(matrix(rnorm(1550),c(50,31))) model <- step(lm(x[,1] ~ as.matrix(x[,2:31]))) --Matt -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of rongguiwong Sent: Monday, September 20, 2004 20:52 PM To: r-help at stat.math.ethz.ch Subject: [R] how to take this experiment with R? This message uses
2010 Feb 14
1
Problem with specifying variance-covariance matrix for random effects (nlme package)
Hi all, I've been struggling with trying to specify a diagnoal matrix for linear mixed effects model. I think I've got nearly everything correct, except the following message appears: In lme.formula(fixed = fwave ~ sex + sexXbulbar + visit + age + : Fewer observations than random effects in all level 1 groups Not sure if i've provided enough details, but I'm basically trying
2003 Feb 12
1
models for square tables
I've posted a sample file for estimating loglinear models for square tables (mobility models) at http://www.xs4all.nl/~jhckx/mcl/R/ Comments and suggestions are welcome. John Hendrickx
2003 Jan 29
3
multinomial conditional logit models
A multinomial logit model can be specified as a conditional logit model after restructuring the data. Doing so gives flexibility in imposing restrictions on the dependent variable. One application is to specify a loglinear model for square tables, e.g. quasi-symmetry or quasi-independence, as a multinomial logit model with covariates. Further details on this technique and examples with several
2004 Nov 06
3
how to read this matrix into R
the following the the lower.tri matrix in a file named luxry.car and i want to read it in R as a lower.tri matrix.how can i do? i have try to use help.search("read"),but no result what i want. 1.000 0.591 1.000 0.356 0.350 1.000
2003 May 14
1
mcl models, percentages
I've put two packages for R on my home page at http://www.xs4all.nl/~jhckx/R/. The "pcnt" package is for multiway percentage tables. I've posted a first effort called "ctab" on this group and a request for enhancing "ftable" with percentages on the wishlist. The "mcl" package is for estimating multinomial logistic models using conditional logistic
2004 Oct 18
3
how to study the code of R
i want to study R programming by studying the existing code from R itself,but i don't know how to read the code,can any one give me some guide? my R is installed in /usr/lib/R/ [ronggui at mylinux ronggui]$ /usr/lib/R/ afm bin doc etc include library modules share > version _ platform i586-mandrake-linux-gnu arch i586 os linux-gnu system i586,
2009 Aug 16
1
How to deal with multicollinearity in mixed models (with lmer)?
Dear R users, I have a problem with multicollinearity in mixed models and I am using lmer in package lme4. From previous mailing list, I learn of a reply "http://www.mail-archive.com/r-help at stat.math.ethz.ch/msg38537.html" which states that if not for interpretation but just for prediction, multicollinearity does not matter much. However, I am using mixed model to interpret something,
2012 Apr 03
1
how to use condition indexes to test multi-collinearity
Dear Users, I try to calculate condition indexes and variance decomposition proportions in order to test for collinearity using colldiag() in perturb package, I got a large index and two variables with large variance decomposition proportions,but one of them is constant item.I also checked the VIF for that variable, the value is small.The result is as follows: Index intercept V1
2007 Jul 18
0
multicollinearity in nlme models
I am working on a nlme model that has multiple fixed effects (linear and nonlinear) with a nonlinear (asymptotic) random effect. asymporig<-function(x,th1,th2)th1*(1-exp(-exp(th2)*x)) asymporigb<-function(x,th1b,th2b)th1b*(1-exp(-exp(th2b)*x)) mod.vol.nlme<-nlme(fa20~(ah*habdiv+ads*ds+ads2*ds2+at*trout)+asymporig(da.p,th1,th2)+ asymporigb(vol,th1b,th2b),
2004 Sep 26
2
how to set options (variables) permanently
Hi, after starting Emacs/ESS/R environment I tried to launch "edit" or "fix". This normally should fire up the $editor, isn't it. Instead of this I regularily I run into an error that there something wrong with $editor. ----------------------------------------------- > op <- options(); str(op) Amongst many entries you'll find this: $ editor
2009 Mar 31
1
Multicollinearity with brglm?
I''m running brglm with binomial loguistic regression. The perhaps multicollinearity-related feature(s) are: (1) the k IVs are all binary categorical, coded as 0 or 1; (2) each row of the IVs contains exactly C (< k) 1''s; (3) k IVs, there are n * k unique rows; (4) when brglm is run, at least 1 IV is reported as involving a singularity. I''ve tried recoding the n
2012 Jul 11
1
Help needed to tackle multicollinearity problem in count data with the help of R
Dear everyone, I'm student of Masters in Statistics (Actuarial) from Central University of Rajasthan, India. I am doing a major project work as a part of the degree. My major project deals with fitting a glm model for the data of car insurance. I'm facing the problem of multicollinearity for this data which is visible by the plotting of data. But I'm not able to test it. In the case
2011 Dec 29
2
3d plotting alternatives. I like persp, but regret the lack of plotmath.
I have been making simple functions to display regressions in a new package called "rockchalk". For 3d illustrations, my functions use persp, and I've grown to like working with it. As an example of the kind of things I like to do, you might consult my lecture on multicollinearity, which is by far the most detailed illustration I've prepared.
2013 Nov 21
1
Regression model
Hi, I'm trying to fit regression model, but there is something wrong with it. The dataset contains 85 observations for 85 students.Those observations are counts of several actions, and dependent variable is final score. More precisely, I have 5 IV and one DV. I'm trying to build regression model to check whether those variables can predict the final score. I'm attaching output of
2016 Apr 15
1
Multicollinearity & Endogeniety : PLSPM
Hi I need a bit of guidance on tests and methods to look for multicollinearity and Endogeniety while using plspm Pl help ------------------ T&R ... Deva [[alternative HTML version deleted]]
2011 Apr 16
0
regression questions (lm, lmer)
Dear all,  I hope this is the right place to ask this question. I am reviewing a research where the analyst(s) are using a linear regression model. The dependent variable (DV) is a continuous measure. The independent variables (IVs) are a mixture of linear and categorical variables. The author investigates whether performance (DV - continuous linear) is a function of age (continuous IV1 -
2006 Oct 23
0
Methods of addressing multicollinearity in multiple linear regression with R
In searching the R help archives I find a number of postings in April of 2005, but nothing since then. If readers are aware of more recent contributions addressing the problems arising from multicollinearity (such as with the bootstrap, jackknife, or other techniques) I would appreciate a reference. Thank you, Ben Fairbank [[alternative HTML version deleted]]
2011 Apr 18
1
regression and lmer
Dear all,  I hope this is the right place to ask this question. I am reviewing a research where the analyst(s) are using a linear regression model. The dependent variable (DV) is a continuous measure. The independent variables (IVs) are a mixture of linear and categorical variables. The author investigates whether performance (DV - continuous linear) is a function of age (continuous IV1 -