[R] Question on funcion and npar

Dear everyone, The following function, taken from Quick-R, gets measures of central tendency and spread for a numeric vector x. I can't figure out what the argument npar means in each instance. Any tips will be most appreciated. mysummary <- function(x, npar=TRUE, print=TRUE) { if (!npar) {

[R] Zero-inflated Negat. Binom. model

Dear R crew: I am sorry this question has been posted before, but I can't seem to solve this problem yet. I have a simple dataset consisting of two variables: cestode intensity and chick size (defined as CAPI). Intensity is a count and clearly overdispersed, with way too many zeroes. I'm inte

[R] Predict from glm

Dear list members, I fitted a glm model (See output below). My outcome is death, and weight (continuous), ClutchSize (3-level factor), EggVolume (continuous), Sex (obviously 2-level factor), and SiblingCompetence (2-level factor) are my covariates. I'd like to obtain the odds of death for a

[R] Dummy variables or factors?

Dear R-people, I am analyzing epidemiological data using GLMM using the lmer package. I usually explore the assumption of linearity of continuous variables in the logit of the outcome by creating 4 categories of the variable, performing a bivariate logistic regression, and then plotting the co

[R] Zero inflated negat. binomial model

Dear R crew: I think I am in the right mailing list. I have a very simple dataset consisting of two variables: cestode intensity and chick size (defined as CAPI). Intensity is clearly overdispersed, with way too many zeroes. I'm interested in looking at the association between these two variab

[R] Multinomial model and p-values

Hello everyone, I have a dataset which consists of "Pathology scores" (Absent, Mild, Severe) as outcome variable, and two main effects: Age (two factors: twenty / thirty days old) and Treatment Group (four factors: infected without ATB; infected + ATB1; infected + ATB2; infected + ATB3). First I

[R] Multivariable model

Hello r-list members, I've been doing some linear modeling with a dataset structured as follows. Tubes containing 500 larvae of Trichinella each were treated with one of four different temperatures. Each day (or every 10 days depending on treatment group), 3 tubes were selected from each treatmen

[R] Subsetting dataframe with missing values

Dear R-community, I am using R (V 2.14.1) on Windows 7. I have a dataset which consists of 19 variables for 91 individuals or rows. Two of my variables are Age (adult/chick, with no NA values) and Sex (0 for females/1 for females, with quite a few NA values). The sex of many adult birds is unknow

[R] Basic help needed

Hello all, New user here. I have R 2.7.1. installed, but don’t have internet access in my PC. Therefore, I downloaded the ISwR package (Introductory Statistics with R) from CRAN and then moved it into my HD. I can’t seem to install the local package under Windows Vista system. I've tried using

[R] Coefficients, OR and 95% CL

Dear R-users, After running a logistic regression, I need to calculate OR by exponentiating the coefficient, and then I need the 95% CL for the OR as well. For the following example (taken from P. Dalaagard's book), what would be the most straightforward method of getting what I need? Could any

[R] Model building using lmer

Dear R-experts, Quite new to R on this end, but learning fast (I hope). I am running version 2.7.1 on Windows Vista. I have small dataset which consists of: # NestID: nest indicator for each chicken. Siblings sharing the same nest have the same nest indicator. # Chick: chick indicator consis

[R] Epicalc package

Dear R-friends,   I am using the epicalc package and the manual by V. Chongsuvivatwong "Analysis of epidemiological data using R and Epicalc" to get the hang of some basic epidemiological analyses.      After running all the analyses of chapter 7, one is supposed to wrap it up by saving the dat

Re: [R] Epicalc package

Dear David, Thank you very much for your help! I think I have solved the issue. Lucho --- On Fri, 11/14/08, David Winsemius <[EMAIL PROTECTED]> wrote: From: David Winsemius <[EMAIL PROTECTED]> Subject: Re: [R] Epicalc package To: "Luciano La Sala" <[EMAIL PROTE

[R] GLMM using lme4

Dear R-experts, I am running R version 2.7.1 on Windows Vista. I have a small dataset which consists of “chick ID”, “year (0, 1)”, “hatching order [HO, defined as first, second and third-hatched chick]”, and the binary outcome of interest “death (0, 1)”. So a subset of my dataset looks like th