[R] Trends for many units
Prof Brian D Ripley
ripley at stats.ox.ac.uk
Fri Jan 5 22:37:25 CET 2001
On Fri, 5 Jan 2001 s-luppescu at uchicago.edu wrote:
> I have data on every grade in all elementary schools in Chicago over 5 years. I
> would like to estimate a trend over time for each grade in each school. There
> are 17,600 data all together (about 460 schools, nearly 8 grades each, over 5
> years). Is there a not-so-hard way to do this in R (I was thinking of using
And the statistical model is? 5 years is a short series, and I would have
thought a multilevel model was appropriate (and in R that means using lme).
I'l leave it to someone who understands the terms (grades are a response
in my terminology) to suggest a model.
rlm and friends assume independent errors, which looks dubious here.
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272860 (secr)
Oxford OX1 3TG, UK Fax: +44 1865 272595
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch
More information about the R-help