similar to: save model summary

I have two regressions to perform - one with a metric DV (-3 to 3), the other with an ordered DV (0,1,2,3). Neither normal distribution not homoscedasticity is given. I have a two questions: (1) Some sources say robust regression take care of both lack of normal distribution and heteroscedasticity, while others say only of normal distribution. What is true? (2) Are there ways of using robust

Hello, I have many hundred variables in my longitudinal dataset and lots of missings. In order to plot data I need to remove missings. If I do > data <- na.omit(data) that will reduce my dataset to 2% of its original size ;) So I only need to listwise delete missings on 3 variables (the ones I am plotting). data$variable1 <-na.omit(data$variable1) does not work. Thank you

I have a question regarding the build of my project papeR (hosted on R-forge http://r-forge.r-project.org/R/?group_id=1574) with respect to lme4. Both, Windows and MacOS are complaining that lme4 doesn't export summary: Error : object 'summary' is not exported by 'namespace:lme4' ERROR: lazy loading failed for package 'papeR' Linux however builds the project

I would like to test in R what regression fits my data best. My dependent variable is a count, and has a lot of zeros. And I would need some help to determine what model and family to use (poisson or quasipoisson, or zero-inflated poisson regression), and how to test the assumptions. 1) Poisson Regression: as far as I understand, the strong assumption is that dependent variable mean = variance.

In the 'doBy' package there is an esticon() function for calculating linear contrasts for various model types. I have defined an S3-method 'esticon.mer()' for 'mer' objects from the lme4 package. Building the package and invoking the method gives: > esticon(fm1, c(1,1)) Confidence interval ( WALD ) level = 0.95 Error in as.integer(x) : cannot coerce type 'S4'

I am running 9 negative binomial regressions with count data. The nine models use 9 different dependent variables - items of a clinical screening instrument - and use the same set of 5 predictors. Goal is to find out whether these predictors have differential effects on the items. Due to various reasons, one being that I want to avoid overfitting models, I need to employ identical types of

Dear list, I have another (again possibly boneheaded) puzzle about importing, again encapsulated in a nearly trivial package. (The package is posted at <http://www.math.mcmaster.ca/bolker/misc/coefsumtest_0.001.tar.gz>.) The package consists (only) of the following S3 method definitions: coeftab <- function(object, ...) UseMethod("coeftab",object) coeftab.default <-

I am currently using the relaimpo package to estimate the relative importance of regressors (N= 4000): > m1 <- lm(y ~ x1+x2+x3+x4+x5+, data=data) > calc.relimp(m1, rela=TRUE) > m2=boot.relimp(m1, boot = 500, rela=TRUE, type="lmg") > booteval.relimp(m2) > plot(booteval.relimp(m2)) In a new dataset with 3 measurement points (0,6,12 weeks), I want to perform a similar

Hi all I have problems in accessing a mer object called model.01 from a workspace that was created with R 2.8.1 and saved with save into an .RData file (on Windows XP or Ubuntu 8.10, don't remember anymore). Now I want to open it in R 2.9.0 on Ubuntu 8.10. I use # load workspace load("name.RData") which seems to work: ls() # all objects in there [1] "all"

I want to call summary on a mer object (from lme4) within my package but I can't seem to get the namespace to import the necessary method. I've simplified my package to this one function: --------------------------- ss <- function(m) { summary(m) } --------------------------- And my namespace file looks like this, where I've attempted to follow the instructions in "Writing

I have a dataset with plenty of variables and lots of missing data. As far as I understand, R automatically removes subjects with missing values. I'm trying to fit a mixed effects model, adding covariate by covariate. I suspect that my sample gets smaller and smaller each time I add a covariate, because more and more lines get deleted. Is there a way of displaying how many subjects are

A colleague wrote the following syntax for me: D = read.csv("x.csv") ## Convert -999 to NA for (k in 1:dim(D)[2]) { I = which(D[,k]==-999) if (length(I) > 0) { D[I,k] = NA } } The dataset has many missing values. I am running several regressions on this dataset, and want to ensure every regression has the same subjects. Thus I want to drop subjects listwise for

I have two very strong fixed effects in a LMM (both continuous variables). model <- lmer( y ~ time + x1+x2 + (time|subject)) Once I fit an interaction of these variables, both main effects disappear and I get a strong interaction effect. model <- lmer( y ~ time + x1*x2 + (time|subject)) I would like to plot this effect now, but have not been able to do so, reading through ggplot2 and

I am having a problem extracting from "mer" objects.    I have constructed my problem using existing datasets.   Using the following commands:   require(lme4) fm1 <- lmer(Yield ~ 1 + (1 | Batch), Dyestuff) fixef(fm1) I get the following error message: "Error in UseMethod("fixef") : no applicable method for "fixef""   I know that "fixef" is in

I am currently attempting to hack the recently featured profileModels package so that it can handle models generated by the lme4 (mixed models) package. I'm getting really confused by different behavior of summary() before and after loading the lme4 package, and inside and outside the profileMethod() function. The basic behavior is that with lme4 loaded, and "obj" a fitted object

Hi all, I've now got a problem with some modified lmer code (function lmer1 pasted at end) - I've made only three changes to the lmer code (marked), and I'm not really looking for comments on this function, but would like to know why execution of the following commands that use it almost invariably (but not quite predictably) leads to the R session terminating. Here's the command

Dear R users, I am trying to fit a GLMM to the following dataset; tab a b c 1 1 0.6 199320100313 2 1 0.8 199427100412 3 1 0.8 199427202112 4 1 0.2 199428100611 5 1 1.0 199428101011 6 1 0.8 199428101111 7 0 0.8 199527103011 8 1 0.6 199527200711 9 0 0.8 199527202411 10 0 0.6 199529100412 11 1 0.2 199626201111 12 2 0.8 199627200612 13 1 0.4 199628100111 14 1 0.8

Hi R-users: New to R and I am trying to run a GLM with random effects. I have 3 replicates ('Replicate) of counts of parasites ('nor.tot.lep') before and after an experiment ('In.Out'). When I run lmer I get the error messages (16 of each) below... > lmer(nor.tot.lep ~ In.Out + (In.Out|Replicate),data=coho, family =tweedie(var.power = 1, + link.power = 1)) Generalized

Probably a stupidly simple question, but I wouldn't know how to google it: xyplot(neuro ~ time | UserID, data=data_sub) creates a proper plot. However, if I add type = "l" the lines do not go first through time1, then time2, then time3 etc but in about 50% of all subjects the lines go through points seemingly random (e.g. from 1 to 4 to 2 to 5 to 3). The lines always start at time

Hi everyone, I'm sure this has been asked before, but I could not find the right search terms to find it. If I want to see what summarizing a model fit with lm() does, I can write "summary.lm". But what if I want to see what summarizing a model fit with lmer() (lme4 package) does? showMethods(summary) Function: summary (package base) object="ANY"