National People Meter sample quality continues at 5-year highs

Nielsen announced some good news about the quality of its National People Meter television ratings panel—they have once again hit five-year highs in sample quality. For the week ending 11/15, the Sample Performance Indicator (SPI), which measures the percentage of people who were originally solicited to join the sample that are actually in it, and are producing useable data, reached its highest levels since May 2004.

In-tab rates, which measure the percent of sets or people that are providing quality data on a given day, continue to reach unprecedented levels. These quality achievements are due to important and significant investments that we have made in meter technology, statistical and methodological research, and field operations. What makes these quality levels even more impressive is the national sample is twice as large as it was five years ago, having grown to over 20,000 total households and 12,300 effective households. In addition, their measurement now features 100% digital measurement, as they are faced with an increasingly complex home television environment with more total and more sophisticated televisions per home.

The details of the record quality metrics include:
Sample Performance Indicator: For the week ending 11/15, the SPI reached 45.9%. It has not reached this level since May, 2004. Nielsen’s average SPI for year-to-date 2009 is 44.4%.

In-Tab Rates
Sets and persons in-tab rates have improved in a similar fashion in 2009, and are holding at unprecedented levels. For the week ending 11/15, the sets in-tab rate was 94.7% and the persons in-tab rate was 92.0%.