similar to: Forcing a reference category in logistic model

Displaying 20 results from an estimated 30000 matches similar to: "Forcing a reference category in logistic model"

2006 Apr 09
1
logistic regression model with non-integer weights
When fitting a logistic regression model using weights I get the following warning > data.model.w <- glm(ABN ~ TR, family=binomial(logit), weights=WEIGHT) Warning message: non-integer #successes in a binomial glm! in: eval(expr, envir, enclos) Details follow *** I have a binary dependent variable of abnormality ABN = T, F, T, T, F, F, F... and a continous predictor TR = 1.962752
2005 Sep 13
1
logistic regression with nominal predictors
(Sorry for obvious mistakes, as I am quite a newby with no Statistics background). My question is going to be what is the gain of logistic regression over odds ratios when none of the input variables is continuous. My experiment: Outcome: ordinal scale, ``quality'' (QUA=1,2,3) Predictors: ``segment'' (SEG) and ``stress'' (STR). SEG is nominal scale with 24
2011 Oct 25
1
Glmnet Logistic Variable Questions
We are workin on building a logistic regression using 1. We are doing a logistic regression with binary outcome variable using a set of predictors that include 8 continuous and 8 category predictors 2. We are trying to implement interaction between two variables (continuous and category or just continuous) The dataset is 200,000 rows and we are using glmnet, how can we model those two points ?
2009 Apr 07
1
Simulate binary data for a logistic regression Monte Carlo
Hello, I am trying to simulate binary outcome data for a logistic regression Monte Carlo study. I need to eventually be able to manipulate the structure of the error term to give groups of observations a random effect. Right now I am just doing a very basic set up to make sure I can recover the parameters properly. I am running into trouble with the code below. It works if you take out the object
2011 Jul 22
4
glmnet with binary logistic regression
Hi all, I am using the glmnet R package to run LASSO with binary logistic regression. I have over 290 samples with outcome data (0 for alive, 1 for dead) and over 230 predictor variables. I currently using LASSO to reduce the number of predictor variables. I am using the cv.glmnet function to do 10-fold cross validation on a sequence of lambda values which I let glmnet determine. I then take
2011 Aug 17
4
How to use PC1 of PCA and dim1 of MCA as a predictor in logistic regression model for data reduction
Hi all, I'm trying to do model reduction for logistic regression. I have 13 predictor (4 continuous variables and 9 binary variables). Using subject matter knowledge, I selected 4 important variables. Regarding the rest 9 variables, I tried to perform data reduction by principal component analysis (PCA). However, 8 of 9 variables were binary and only one continuous. I transformed the data by
2003 May 11
1
NLME - multilevel model using binary outcome - logistic regression
Hi! I'm pretty raw when working with the R models (linear or not). I'm wondering has anybody worked with the NLME library and dichotomous outcomes. I have a binary outcome variable that I woul like to model in a nested (multilevel) model. I started to fit a logistic model to a NLS function, but could not suceed. I know there are better ways to do it in R with either the LRM or GLM wih
2011 Jun 22
2
VGAM constraints-related puzzle
Hello R users, I have a puzzle with the VGAM package, on my first excursion into generalized additive models, in that this very nice package seems to want to do either more or less than what I want. Precisely, I have a 4-component outcome, y, and am fitting multinomial logistic regression with one predictor x. What I would like to find out is, is there a single nonlinear function f(x) which acts
2012 Jun 08
1
Testing relationships in logistic regression
I am interested in knowing whether and how I can test the significance of the relationship between my continuous predictor variable (a covariate) and my binary response variable according to two different groups, my categorical predictor variable, in a logistic regression model (glm). Specifically, can I determine whether the relationships are identical (the hypothesis of coincidence), or whether
2011 Nov 25
1
variable types - logistic regression
Hello, Is there an example out there that shows how to treat each of the predictor variable types when doing logistic regression in R? Something like this: glm(y~x1+x2+x3+x4, data=mydata, family=binomial(link="logit"), na.action=na.pass) I'm drawing mostly from: http://www.ats.ucla.edu/stat/r/dae/logit.htm ...but there are only two types of variable in the example given. I'm
2011 Aug 25
1
Syntax for a three-level logistic model
Dear People at R help, I am trying to figure out the syntax for a three-level logistic model with a single random effect (intercept): Data Collected My data consist of three levels: level 1 is four setting for each student (setting nested within student), and each student is registered in one of 14 universities (students nested within university). More detailed: A. 2,479 students who have a
2008 May 16
1
SE of difference in fitted probabilities from logistic model.
I am fitting a logistic binomial model of the form glm(y ~ a*x,family=binomial) where a is a factor (with 5 levels) and x is a continuous predictor. To assess how much ``impact'' x has, I want to compare the fitted success probability when x = its maximum value with the fitted probability when x = its mean value. (The mean and the max are to be taken by level of the factor
2010 Dec 29
1
logistic regression with response 0,1
Dear Masters, first I'd like to wish u all a great 2011 and happy holydays by now, second (here it come the boring stuff) I have a question to which I hope u would answer: I run a logistic regression by glm(), on the following data type (y1=1,x1=x1); (y2=0,x2=x2);......(yn=0,xn=xn), where the response (y) is abinary outcome on 0,1 amd x is any explanatory variable (continuous or not)
2007 May 08
3
ordered logistic regression with random effects. Howto?
I'd like to estimate an ordinal logistic regression with a random effect for a grouping variable. I do not find a pre-packaged algorithm for this. I've found methods glmmML (package: glmmML) and lmer (package: lme4) both work fine with dichotomous dependent variables. I'd like a model similar to polr (package: MASS) or lrm (package: Design) that allows random effects. I was
2009 Jun 22
1
How to make try to catch warnings in logistic glm
Dear list, >From an earlier post I got the impression that one could promote warnings from a glm to errors (presumably by putting options(warn=1)?), then try() would flag them as errors. I?ve spent half the day trying to do this, but no luck. Do you have an explicit solution? My problems is that I am trying to figure out during what conditions one may find 5 significant parameters in a
2007 Nov 13
1
FW: Reference category for explanatory factors
(Oops first mistake was posting to the wrong area) I am not sure what is needed to be posted in terms of what I have done but will explain nonetheless. I am using the msm.package and trying to specify my reference category for an outcome covariate. The following command line works: ## age of respondent - using year5a: categorical preg_fyear5a.msm<-msm(outcome~ipi, subject=id, data,
2012 Oct 23
3
Error in contrasts message when using logistic regression code.
I have a rather large data set (about 30 predictor variables) I need to preform a logistic regression on this data. My response variable is binary. My code looks like this: mylogit <- glm(Enrolled ~ A + B + C + ... + EE, data = data, family = binomial(link="logit")) with A,B,C, ... as my predictor variables. Some categorical, some continuous, some binary. I run the code and get
2008 Apr 20
1
Stepwise logistic regression....take too long...
Dear R helpers, I'm trying to build logistic regression model large dataset 360 factors and 850 observations. All 360 factors are known to be good predictors of outcome variable but I have to find best model with maximum 10 factors. I tried to fit full model and use stepAIC function to get best model but unfortenatly, the process takes too long to complete (more than 4 hours)... Is it
2013 May 24
1
Multinomial logistic regression
Is it possible to use function "glm" in case when my outcome variable has 5 different classes? I have seen examples only when using binomial outcome variable. What about using function "multinom"? How do I to get the signifigance and the confidence levels of the coefficients and the value of goodness of the model with this function? Thank You for Your help! -- View this
2009 Aug 12
1
what is the difference between the two logistic models?
Hi All, I have data with 400 individuals and the following information Grade: pass or fail coded as 1 for pass and 0 for fail Sex: male or female ( coded as 1 for male and 2 for female ) Age Teaching.method : can be 1,2,3 I want to fit a logistic regression where the outcome if (1=pass or 0 for fail) and the rest of the variables are the regressors. My question is that I am not sure