[R] classification accuracy in logistic regression

[Frank E Harrell Jr]

Achim Zeileis wrote:
> On Thu, 20 Nov 2008, David Kaplan wrote:
> 
>> Hi all,
>>
>> I'm looking for a program that will take the predicted probabilities 
>> from a logistic regression using glm{stats}, dichotomize them 
>> according to a threshold that I can control, and then use them to form 
>> sensitivity, specificity, false pos and false neg rates.
> 
> I would look at the ROCR package on CRAN which provides convenient 
> access to various measures and associated graphics.
> Z

But be very skeptical about the operating characteristics of these 
operating characteristics.

Frank Harrell

> 
>> Thanks in advance.
>>
>> David
>>
>>
>> -- 
>> =======================================================================
>> David Kaplan, Ph.D.
>> Professor
>> Department of Educational Psychology
>> University of Wisconsin - Madison
>> Educational Sciences, Room, 1061
>> 1025 W. Johnson Street
>> Madison, WI 53706
>>
>> email: dkaplan at education.wisc.edu
>> homepage:
>> http://www.education.wisc.edu/edpsych/default.aspx?content=kaplan.html
>> Phone: 608-262-0836
>>
>> ______________________________________________
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>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
> 
> ______________________________________________
> R-help at 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.
> 


-- 
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University