[R] Plotting confidence bands around regression line

[Michal Figurski]

David,

I may have stated my problem incorrectly - my problem is to *obtain the 
coordinates* for confidence boundary lines. As input data I have only 
CIs for slope and intercept.

rms/Hmisc packages are very nice, but unfortunately they do not work 
with Passing-Bablok nor 'nls' models.

--
Michal J. Figurski, PhD
HUP, Pathology & Laboratory Medicine
Biomarker Research Laboratory
3400 Spruce St. 7 Maloney
Philadelphia, PA 19104
tel. (215) 662-3413

W dniu 2010-08-10 11:09, David Winsemius pisze:
>
> 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.
>