Arbitron's sampling methodologyisFARmoreimportantthanMrorMrsDePetro's misdeeds

[Roger Kirk]

Sid Schweiger wrote:
> As I understand it, it will shut off after a certain interval (I want to say three hours, but I could be wrong about that).  Supposedly it is sensitive enough to detect the rise and fall of the chest of someone who is breathing, which is why Arbitron insists that the respondent *wear* it.
>   
How big is this PPM?  Any Web Site with pictures?