How do they know if you're watching a show or recording it?

[Fritzo]

I always read on my favorite shows "ratings are down because people are using Tivos and PVR's to record shows instead of watching them". How do they know this? The tuner on the PVR tunes into the show...for all they know I'm watching it WHILE it's recording.

 

[Canai]

It's the little cameras they have inside every tv.

 

[Bootprint]

Don't Tivos provide feedback to the company?

Nielsen Ratings

 

[thirdeye]

The device still has to be "tuned" into the channel to record it.