steve wrote:

> Tim Wescott wrote:
>
>
>>Quantifiable in both cases -- you take the original signal and the
>>corrupted one, you calculate the 'badness' of the corruption by whatever
>>criteria is important to your problem at hand, and you compare the two
>>numbers (hopefully you can reduce the corruption down to a number).
>>
>
> no I meant analytically, in the general case, not by experiment
>
One ought to be able to do it either analytically or by experiment.
Usually when I do this kind of stuff I do both -- analytically to make
sure I understand the problem, then experimentally to verify that my
analysis was correct and later to verify that my implementation was also
correct.
>
>>In the case of the EKG what's important (AFAIK) is the size and timing
>>of the roundish humps that occur before and after the great big spike.
>>If your anti-aliasing filters are contributing roundish humps of their
>>own, then that's a bad thing because it knocks the pattern recognition
>>element (the doctor's brain) for a loop. In this particular case it is
>>very important not to have artifacts from the spike either before or
>>after the spike --
>
>
> I don't know, this doesn't make any sense to me, the artifacts
> generated by aliasing doesn't guarantee specific signal corruption
> won't happen, which you seem to imply
>
I didn't mean to. Artifact == corruption, in this context.

--

Tim Wescott
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