But that IS the point these decisions are based on numbers that are at best a "guess" which is more than absurd in this day and age.
Any Desktop recording unit like TIVOs and DVRs as well as Cable Boxes (non record/time-shifting ones) and Sat Boxes have the capability to accurately measure Exactly what is shown on the TV screen. And such a system would eliminate much of the Bias built into Nielsen's system. But inertia STOPS the usage of this new technology (also there has been a move in the minority communities to stop a changeover to the more accurate system being that Nielsen over samples many of the minority communities to escape criticism.)
Basically the Nielsen system is akin to a cartel controlling exactly who gets the goodies. Its far from the "free Market" because the scoring methods are faulty and in some cases down right biased.
But that doesn’t matter. Here’s the basic reality: the Nielsen numbers decide the ad price, if the Nielsen numbers are bad the show gets canceled, whether the Nielsen numbers have anything at all to do with the number of people watching the show is completely besides the point. Those numbers are ALL that matters, and until a network decides to get their numbers and manages to convince their advertisers that the other way is at least as good as they think Nielsen is nothing else matters, nothing else even comes close to maybe mattering.
It is a free market, the numbers decide, just because you and I and everybody else on the planet that not in the business thinks the numbers are a fiction doesn’t change the basic facts.