Pew: Growing Cell Phone Poll Bias Favors Republicans

[JohnWxy]

http://www.huffingtonpost.com/2010/10/13/pew-research-cell-phone-p_n_761760.html



Does it matter that many polls -- including the vast majority that we are currently watching at the state and congressional district level -- do not call Americans who use only a cell phone and thus lack landline telephone service? Yes it does. It creates a growing bias that appears to benefit Republican candidates. That's the message of a new analysis released this afternoon by the Pew Research Center.

Since 2006, a rapidly increasing percentage of American households lacks landline phone service. The most recent government estimates find that one in four American households is reachable by cell phone only. Pollsters have been reluctant to sample and call Americans on their cell phones, partly because it costs more and partly because federal law requires hand dialing any call placed to a cell phone, which makes such calls less efficient and puts cell phone polling off limits to automated survey methodologies.

For the last four years, the Pew Research Center has conducted public opinion surveys involving separate, parallel samples of both landline and mobile phones. Their design allows for a comparison between combined samples of landline and cell interviews and samples based only on landline calls.

Before the 2008 election, they found that calling only landline phones introduced a "small but real" bias in favor of John McCain, an average bias of 2.3 percentage points on the margin on nine national surveys conducted between June and October of that year.
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[CurtEastPoint]

1. OOPS... I did misread it...

Sorry.

[benddem]

2. HUH?

this doesn't say anything about cell phone users...it says that cell phone (only) users aren't polled and cell phone users are younger and possibly Democrats. Read the article!!!!

[elleng]

6. Knew that!

[glitch]

3. Suspected for years, good to see it confirmed. Thanks for posting K & R nt

[Qutzupalotl]

4. "benefits Republicans" -- until they see the election returns!

They could be in for a surprise!

Many here have said the younger demographics are going cell-only, and they tend to vote D. That's gotta be good for a couple of points in close races...provided the media haven't discouraged our side too much. Fear of a lunatic takeover could be a good motivator.

[toddwv]

7. Could be more than a couple of points

"the Pew Center finds that sampling only landline phones creates an even bigger bias -- 'differences of four to six points on the margin' - in favor of the Republicans.

[bemildred]

5. Look, the "likely voter" stuff is already biased, a biased sample.

It excludes new voters, and returning voters, as a statistical sampling methodology it is already very flawed, already making conservative assumptions about the outcome, and it excludes precisely the voters that are motivated by current events to vote for change. If you want good statistics, you need RANDOM samples from the WHOLE population.