[time-nuts] Allan variance Vs Plain Old Accuracy

[Angus]

On Thu, 14 Feb 2008 11:00:32 -0000, you wrote:

>Hi All,
>
>This comment is bound to get you all going.
>
>Maybe I'm being stupid, but why does everyone use Allan Variance and not
>plan old accuracy?
>
>I am very familiar with David Allan's full article on Allan Variance.
>However Allan Variance isn't the same as accuracy.
>
>Accuracy is what is important to most people.  And that's not RMS but peak
>to peak, e.g worse case.  And not averaged over 24 hours but averaged over 1
>second or less.

Something I rather miss is some good old phase or frequency plots -
especially if done at different timescales - which seem to be becoming
rather less common now. 
As well as having a plot of ADEV or its relations, seeing what the
reference is doing and when is useful, and most ADEV plots using so
few values of tau does not help.

Angus.