Readme file

SERIES B 
Statistical Methodology

Weight empirical adaptive variance estimators for correlated data regression,
T. Lumley and P. Heagerty
Journal of the Royal Statistical Society, Series B, Statistical Methodology, Volume 61 (1999)

The file glmweave.R contains code to compute WEAVE standard errors inS-PLUS or R for generalised linear models fitted to time series or data with crossed random effects, and code for sandwich varianceestimators for clustered and longitudinal data.

To use the code load it with the source() command. All the functions take a glm object as the main argument and return either a covariance matrix or a list containing a covariance matrix, bias correction and approximate degrees of freedom. Complete on-line documentation in HTML, S-PLUS or R format is available from:
http://www.biostat.washington.edu/~thomas/weave.html

jack.glm(glm.object,groups),infjack.glm(glm.object,groups)

Variance estimates for independence working models fitted to clustered data. The first is based on the one-step jackknife, the second is the GEE sandwich estimator based on the infinitesimal jackknife.

newey.west.glm(glm.object,times,lag,clag)

Newey-West estimator for estimating equations fitted to time seriesdata. The truncation lag (lag=) optimally increases as the cube root of sample size, you can specify the multiplier (clag=) instead of lag=.

kernelvar.glm<-function(glm.obj,times, lag=NULL,clag=NULL, kernel=c("tukey","bartlett","parzen"))

Estimator based on specified weight function: "bartlett" gives Newey-West estimator, other two are better. If clag= is specified the truncation lag is clag*n^a where a=1/3 for "bartlett", 1/5 for the other kernels.

weightvar.glm<-function(glm.obj,times,weights)

Roll your own. Specify a vector of weights for lags 0:M weave.trunc(glm.obj,times, lag=NULL, ctrunc=4)weighted empirical adaptive variance estimate with weights (n*rho^2>ctrunc) or with weights 1 up to lag=lag, 0 further away weave.smooth(glm.obj,times,csmooth=1) weighted empirical adaptive variance estimate with weightsmin(1,csmooth*N*rho^2)

lele.glm(glm.obj,times,lag)

One-step version of Lele's estimating equation jackknife for time series.

xeffect.glm(glm.obj,g1,g2)

Sandwich standard errors for a crossed design where observations are correlated if they share the same value of g1 or of g2. Unbalanced or incomplete designs are fine.

contact address:

T. Lumley
Department of Biostatistics
University of Washington
Box 357232
Seattle
WA 98195-7232
USA

E-mail: thomas@biostat.washington.edu

Journals

SERIES A
Statistics in Society

SERIES B
Statistical Methodology

SERIES C
Applied Statistics

SERIES D
The Statistician