Cellphones Challenge Poll Sampling

CELLPHONES CHALLENGE POLL SAMPLING
[SOURCE: New York Times, AUTHOR: Megan Thee]
With more American households giving up their old-fashioned land lines and using cellphones for all calls, public opinion researchers are facing a challenge of how to make sure they are getting representative samples when conducting polls. Since the 1970s, pollsters have relied on sampling techniques that depend on talking with people on their home land line telephones. For the most part, the polls sample the public by randomly dialing telephone numbers in every region from a list of area codes and exchanges known to be residences. The sample is weighted to the results of the latest census. But cellphones are not geographically based, forcing pollsters to adjust their methods. In addition, a land line often represents a household and a cellphone often represents an individual. Pollsters say they are also concerned about low response rates among people reached on cellphones. Because wireless carriers charge customers by the minute, people may be less likely to agree to complete lengthy cellphone surveys. The survey industry is exploring reimbursing respondents for minutes used. Researchers using computers to dial may encounter legal complications. The Federal Communications Commission requires an interviewer to dial the number when calling a cellphone. No autodialers are allowed.
http://www.nytimes.com/2007/12/07/us/07polling.html?ref=todayspaper
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