Date: Tue, 5 Jan 2010 11:07:22 -0500
Reply-To: "Keintz, H. Mark" <mkeintz@WHARTON.UPENN.EDU>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: "Keintz, H. Mark" <mkeintz@WHARTON.UPENN.EDU>
Subject: Re: New Comparison Operators? - WAS: missing numerical values = -
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> -----Original Message-----
> From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of
> Sent: Tuesday, January 05, 2010 8:15 AM
> To: SAS-L@LISTSERV.UGA.EDU
> Subject: Re: New Comparison Operators? - WAS: missing numerical values
> = -
> "Jonathan Goldberg" <jgoldberg@BIOMEDSYS.COM> wrote in message
> >I gave an (and who knows, maybe the) explanation in a post on the old
> > thread before I noticed this new one. For ease of reference, here it
> > again.
> > ---------------------------------------
> > This is a hoary question. Logically speaking, having x < 2500
> resolve to
> > true when x is missing is absurd, and having x = y resolve to true
> > both x and y are missing is ludicrous. Missing means "I don't know."
> > x and y are heights, you are claiming that you know that two heights
> > equal when you don't know what either of them is.
> At the risk of seeming the fool, I've always thought of it as:
> if X = "I don't know" and y = "I don't know" then x does equal y.
That is a research or analysis issue, and is context sensitive.
For many SAS users, it is not simply a question of mathematical logic.