On Aug 10, 2010, at 10:56 AM, Michal Figurski wrote:
Dear R-helpers and graphics gurus,
I have two problems with plotting confidence bands:
1. First is relatively simple. I am using the Passing-Bablok
procedure to obtain "unbiased" regression coefficients. This
procedure yields the "a" & "b" coefficient values along with their
confidence intervals. I then plot the raw data with the regression
line, but I would like to add the confidence band for the line...
and I can't figure out how to do it.
In other words, given:
Estimate 5%CI 95%CI
Intercept -4.305562 -9.931152 -1.381792
Slope 1.257318 1.053025 1.678516
How to plot the regression line with confidence band?
Take a look at plotCI in either gplots or plotrix packages.
Harrell's rms/Hmisc packages are nicely integrated with lattice and
encourage you to create effective displays of models that remove
simplistic linearity assumptions.
--
David.
2. Second problem is plotting confidence bands along fitted "nls"
regression line. I tried "predict(nls.object, int='c')" - but
doesn't work. Later I figured in the documentation that the 'int'
parameter is currently ignored. I guess this means it's not a
trivial thing to do. Does anyone have a suggestion on how to obtain
confidence predictions for such a model?
Please cc my email address when you reply. Thanks and best regards,
--
Michal J. Figurski, PhD
HUP, Pathology & Laboratory Medicine
Biomarker Research Laboratory
3400 Spruce St. 7 Maloney
Philadelphia, PA 19104
tel. (215) 662-3413
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
David Winsemius, MD
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
