From pdalgd at gmail.com  Wed Feb 13 13:25:09 2013
From: pdalgd at gmail.com (peter dalgaard)
Date: Wed, 13 Feb 2013 13:25:09 +0100
Subject: [Rd] Regression stars
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On Feb 12, 2013, at 20:19 , Duncan Murdoch wrote:

> I think you are misreading what Peter wrote.  He wasn't defending that point of view, he was describing it.
> 

Yes. However, that being said, there is the point that the whole thing has been designed to work within the paradigm that I described, and, for better or worse, things are reasonably coherent and consistent within that framework.

The thing that always worries me, when people get bothered by some aspect of software design, is that, if you change only that aspect, you may find yourself with something that is incoherent and inconsistent. I have quite a few times found myself realizing that "Uncle John was right after all".  

For instance, if you change the paradigm to say that "character variables are character, unless explicitly turned into factors", and then ameliorate the inconvenience by changing code that relies on factors to convert character variables on the fly, then you will lose the otherwise automatic consistency of level sets between subsets of data. (So, the math department not only has zero female professors, the entire female gender ceases to exist for that subgroup.)

-- 
Peter Dalgaard, Professor
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com



[Rd] Regression stars
peter dalgaard