If You're Watching TV, Raise Your Hand!

The business of figuring out who is watching what on television is increasingly complicated. Channel surfers watch 10 minutes of this station, 30 seconds of that station, and then flips through a dozen other stations. Viewers watching their favorite shows may be extremely successful at avoiding the ads. Still others are watching online or in other ways.

Nielsen Media Research, which has long measured television audiences, is straining to keep up with the new ways that we are watching television. National Public Radio reports.