Election Section
Voter polls conducted with interviews, telephone calls
Voter News Service, a cooperative of The Associated Press, ABC, CBS, CNN, Fox and NBC, conducted its exit poll in the California general election by interviewing 2,710 voters either as they left polling places in 50 precincts statewide Tuesday or by telephone during the past week.
For the Election Day survey, each poll precinct was picked randomly in a process that was ordered to reflect state geography and past vote by party.
As people left voting booths, VNS interviewers asked them to fill out a confidential questionnaire. Voters were chosen at a set interval – such as every fifth person – so that each voter had an equal chance of being picked.
VNS also conducted a telephone poll to interview people who voted early or by absentee ballot. Results from the telephone poll were weighted so that those responses represented 25 percent of the sample, the estimated size of the pre-Election Day vote in California.
In addition to weighting for telephone interviews, the results were adjusted to reflect the different probabilities of selecting a precinct and a voter within each precinct, as well as by the observed sex, race and estimated age of voters who refused to participate.
As with any poll, the results could vary because of chance variations in the sample. For this poll, there was one chance in 20 that sampling error would cause the results to vary by more than 2.5 percentage points either way from the opinions of all voters who participated in the state’s election. The error margin was higher for subgroups in the sample.
Polls are subject to other sources of error, such as from question wording or order.