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Date: Fri, 15 Jul 2011 21:04:10 +1000
Subject: Re: None versus MISSING sentinel -- request for design feedback
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:9537

On Fri, Jul 15, 2011 at 8:46 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> In general, you have missing values in statistics because somebody wouldn't
> answer a question, and the Ethics Committee frowns on researchers torturing
> their subjects to get information. They make you fill out forms.
>

Which, then, is in support of an explicit "User chose not to answer
this question" MISSING value.

ChrisA