Complete poll results and comments:
Number of People Interviewed: 907 Bay Area Residents
Interview Dates: May 30 - June 5, 2008
Conducted Online by: Hertz Research, Petaluma, CA
How ABC7 Listens Polls are Conducted and Potential Sources of Error
ABC7 Listens Polls are conducted by Hertz Research of Petaluma, California. The polls are conducted online among Bay Area residents who registered in advance to participate in the ABC7 Listens Polling program. In order to create samples as representative of the entire Bay Area population as possible, the results for each poll are statistically weighted using a variety of demographic factors provided by respondents during the registration process. These statistical weighting procedures also take into account differences between groups of people who tend to use or not use the Internet.
Regardless of methodology, all polls are potentially affected by a number of factors that may influence their accuracy. A common source for survey inaccuracy is sampling error. The number of respondents largely determines sampling error. Statistical theory indicates that in the case of a poll with this sample size (907 Total Interviews), 95 percent of the time the results of a survey of this size would be the same as interviewing the entire population of the Bay Area, give or take approximately four percent. This is not a probability sample.
However, other sources of error also can impact the accuracy of poll results conducted online and with other techniques. These include but are not limited to the percentage of the population choosing to participate, the likelihood a possible respondent is at home or connected to the Internet, the wording, and ordering of questions, and the techniques used to determine possible survey participants and likely voters. The cumulative impact of all of these potential sources of error is impossible to assess precisely.