Spectrum data model: accuracy

[Alberto Micol]

On Sep 15, 2006, at 13:42, Anita Richards wrote:

>
> In reply to Alberto and in praise of UNKNOWN:
>
>>> Location.Value =  1975 Jan 1
>>> Bounds.Extent = 10 years
>>
>> This is very confusing.
>> If the date is not know very precisely, the accuracy must be not  
>> zero.
>> The accuracy, in this sense, is linked to the concept of "how
>> well I know this measurement", hence it is linked to the Error.
>>
>> The bounds are not errors. The bounds tell the starting point and the
>> ending point (and each with its own error) of a property of an  
>> observations,
>> and have nothing to do with the precision with which we know the  
>> location.
>>
>> Bounds.Extent = 10 years means that the observation spanned across  
>> 10 years,
>> and the user will think that the spectrum is a co-addition or  
>> anyway an assembly
>> of spectra taken within 10 years.
>
> Actually the intended interpretation of Bounds is not that data  
> were taken continuously within the Bounds, but that the data occur  
> somewhere inside the bounds.  I sympathise that it could be  
> confusing, but in Char we decided not to have errors on Bounds; the  
> Bounds are themselves the outer limits to all errors, in a sense.

Just to clarify that I meant not to add errors to bounds;
instead in this case I think that the Location.Value is 1975,
and the Location Error is 10 years.

Ciao,

Alberto