It's not a level playing field, but it's un-level for everyone involved, is I believe, how it goes..  But isn't an unlevel playing field also called a crooked one? 

[Via MRM] (US)

How many PPMs does Nielsen allow in one household? Answer – up to 16. Does that sound large? One current in-tab household has 13 meters, and nine of them belong to people under the age of 17. Nielsen likes stability on the panel, and this particular household has been in the sample for quite a while. Imagine replacing them when they leave after as much as a two-year tenure. That will require placement into multiple households to achieve 13 new meter-carriers, and it costs Nielsen money. But a couple of stations in Nielsen markets aren’t crazy about the possibility of one household with more than a dozen PPMs. We know that younger children can be influenced by the media behavior of their parents or older siblings, for instance. Subscribers aren’t allowed to know the identity of panel members.

According to 2015 data, the percentage of U.S. households containing 7 or more persons is a mere 1.39%. The fraction of households containing more than 10 must be tiny. So what is the possible logic in entertaining the made-up threshold of 16?

There can be only one: It’s a huge bounty for Nielsen to be able to park a large number of meters in a single household like this. It’s comparatively cheap to install and maintain them, and to any radio station subscriber 16 meters all in one household look just like 16 meters in 16 different households – unless you care about the accuracy of the results, of course.

And because these large households are so scarce, where they occur they will represent a HUGE proportion of the installed households in the zips they reside in, if not ALL of them.

I challenge you: Go to ANY one household in any one zip code and tell me if you think that accurately represents all households in that zip code. I dare you.

Now go to any one 16-person household and tell me if you think that accurately represents anything average or typical.

This doesn’t happen that often, Nielsen might say. But how often? You don’t know, do you? I’ll bet the average household size of a Nielsen panelist is larger than the average household size in America. Want to bet me?

And it’s not just about 16 or 10 or even 8.
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