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(I changed subject of this thread, it was "uncertainty".)

 

Thanks, Ed. 

 

First,

we have the characters  ?  and ~ to mean  "questionable" and "approximate".

 

I have been using "questionable"  while others are using "uncertain",  and
we should settle on one or the other. I have no problem switching to
"uncertain" .

 

So let's say: the characters  ?  and ~  mean  "uncertain" and "approximate".

 

Next ..

We could immediately follow ? and ~ with a measure of uncertainly or
precision respectively.   

 

Of course we need to  do it in a manner that (1) doesn't introduce syntactic
ambiguities, and (2) meets  semantic objectives.

 

Take "uncertainty" first.    If we say that ? may be followed by a measure
of uncertainty we have to be careful because ? does not always end the
entire string.  For example: (2004)?06-1.  However if we say that
uncertainty is indicated by one of the letters a, b, c, d, e, then we don't
introduce ambiguity because in the current draft there isn't any case where
? would be followed by one of these letters.

 

So the question is:  Are Ed's suggested set of values acceptable to indicate
uncertainty:

- a) Known to be correct (observed, documented etc.) 
- b) Likely correct ( p> 50%) 
- c) Possibly correct (Might be but not likely) 
- d) Likely incorrect (The date is expected to be wrong p ~ 0) 
- e) Unknown (certainty unknown).

Actually I would eliminate (e); "certainty unknown" should be the default -
it should not be mandatory for the ? to be followed  by an uncertainly
level.  

 

Next, precision.  Similarly, ~ could be followed by a level of precision.
Simon, would you like to propose a scheme?

 

--Ray

 

 

 

 

From: Discussion of the Developing Date/Time Standards
[mailto:[log in to unmask]] On Behalf Of Edward C. Zimmermann
Sent: Tuesday, February 01, 2011 10:22 AM
To: [log in to unmask]
Subject: Re: [DATETIME] uncertainty

 

On Tue, 1 Feb 2011 08:57:29 -0500, Ray Denenberg wrote 
> Ed - can you repost your model.  (I agree, we should refer to it as
"reliability".)   --Ray 

 

I wrote last Nov. 

"We could be crazy and add grade of certainty and data-quality:

- a) Known to be correct (observed, documented etc.) 
- b) Likely correct ( p> 50%) 
- c) Possibly correct (Might be but not likely) 
- d) Likely incorrect (The date is expected to be wrong p ~ 0) 
- e) Unknown (certainty unknown).

(1985)? with the grade (a) is equivalent to 1985.

198u says that its known (a) that the date in the 1980s. The 'u' says we
know 
nothing more.

Going back to by example about the date of the Great Flood and the birthdate

of... "

There are well other nauances of data reliability but I think with the
qualitative segments of observed/documented (highly certain), likely OK,
possibly OK, likely wrong and who knows one probably covers the typical
conversational predicates..  

> 

  


> 
> From: Discussion of the Developing Date/Time Standards
[mailto:[log in to unmask]] On Behalf Of Edward C. Zimmermann 
> Sent: Tuesday, February 01, 2011 7:29 AM 
> To: [log in to unmask] 
> Subject: Re: [DATETIME] uncertainty 


> 

 


> If uncertainty one must start off with a model of how to describe
uncertainty. I provided one such model some time ago. There are others. That
is the starting point. I see these as modifiers to our unknown predicate.
The term really should be "reliability" rather than unknown or uncertain. A
date, after all, that is unknown is unknown. Reliability and trust in the
correctness of a given date, by contrast, can be qualitatively described: a
continuum from probably wrong to highly certain. 




-- 

Edward C. Zimmermann, NONMONOTONIC LAB 
http://www.nonmonotonic.net <http://www.nonmonotonic.net/>  
Umsatz-St-ID: DE130492967