Hmmm: The Cell Phone Effect

As a follow-up to my earlier posting on the Reverse Bradley Effect here is a cobbled together explanation from Fivethirtyeight.com of the Cell Phone Effect...(hint: it works in Obama's favor)

The Cell Phone Effect is caused by the fact that many voters are unreachable to pollsters whose samples consist of landline numbers only. The basic issue with cellphone-only households is that their incidence is not distributed evenly throughout the population. Minorities are more likely to be cellphone-only than whites, and men are more likely to be cellphone-only than women. But the most important differences are in terms of the age of the voter. Fully half of all adults under the age of 30 fall into the cellphone-only or cellphone-mostly buckets, and the number is growing every day. About a third of adults aged 30-44 are cellphone-only or cellphone-mostly.

The first and more commonly-discussed problem is that the cellphone-only voters may not be the same as their landline counterparts. For example, urban voters are about 50 percent more likely to be cellphone-only than rural voters. Thus, a pollster may wind up with a biased sample.

Gallup, Pew and ABC/WaPo have each found a favorable cellphone effect for Obama of between 1-3 points when they have conducted experiments involving polling with and without a cellphone supplement.

Bottom line...for some of those polls your seeing now, add about 2 more points to Obama's total.