Media Daily News’ Wayne Friedman writes that Nielsen is planning on making some changes to how it samples viewers via the National People Meter Panel…

While the total new sample size will be 37,000 homes for NPM in 2011, Nielsen says the “effective” sample size will actually be 17,000 households, taking into account weighting of geographical distribution of the 56 local markets that have Local People Meters. Nielsen says the “effective” sample size of the NPM sample is now 10,000 homes.

As does Media Week’s Katy Bachman…

As Nielsen rolls out more local people meter markets, it will be able to gradually increase the national sample. The expansion for the national sample begins this November when three LPM markets will be integrated into the national sample.

The sample expansion also has implications for Nielsen’s A2/M2 initiative to measure all video. “Our plans for out-of-home viewing, streaming video on the Internet, and the ‘third screen’ devices such as cell phones and hand-held video players, are based on integrating these measurements with traditional television measurement. This much larger national sample creates the necessary foundation for an integrated measurement approach,” said Scott Springer, product leader of audience measurement for The Nielsen Company’s media segment.