[Asterisk-Users] MOS Scores and LCR

[Steve Underwood]

trixter aka Bret McDanel wrote:

>On Sat, 2006-06-17 at 23:25 +0800, Steve Underwood wrote:
>  
>
>>Calling MOS totally subjective is rather strange. Telephony only has to 
>>meet subjective goals. In reality, MOS is pretty objective, as it is a 
>>carefully controlled experiment across enough subjective individuals to 
>>filter out a reasonably objective answer.
>>
>>    
>>
>it is subjective to the particular test, which afaik MOS doesnt have
>standards on what types of people should form such a test group.  As
>such you can have different results based on the combination of the
>sample sounds and the group that is listening to it.  This is why many
>people are typically involved, but that is not a guarantee that the
>group will be diverse enough and objective enough when rating stuff, it
>is just a mitigating factor against all out bias.
>  
>
MOS scores, conducted properly are surprisingly repeatable. They take 
several man years when conducted properly, though, so they don't get 
repeated very often. They are also the only measure that means a damn 
for anything like codec performance. What you are looking for is 
something quite different - a measure of whether the system is giving 
the performance the long and tediously produced MOS score say is 
possible. Many relatively simple things can give you a reasonable handle 
on that.

Regards,
Steve