The survey findings presented in this release are based on the results of
interviews conducted August 4 - 10, 2008. The interviews were conducted at the
Center for Opinion Research at Franklin & Marshall College under the direction
of the poll’s Director, Dr. G. Terry Madonna, Head Methodologist, Berwood
Yost, and Project Manager, Jennifer Harding. The data included in this release
represent the responses of 641 adult residents of Pennsylvania who are currently
registered to vote. Telephone numbers for the survey were generated using
random digit dialing, and respondents were randomly selected from within each
household. Final survey results were weighted to adjust for different selection
probabilities and non-response.
The sample error for registered adults is +/- 3.9 percent. In addition to
sampling error, this poll is also subject to other sources of non-sampling error.
Generally speaking, two sources of error concern researchers most. Non-response
bias is created when selected participants either choose not to participate in the
survey or are unavailable for interviewing. Response errors are the product of the
question and answer process. Surveys that rely on self-reported behaviors and
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attitudes are susceptible to biases related to the way respondents process and
respond to survey questions.
This Franklin & Marshall College Poll is produced in conjunction with the
Philadelphia Daily News, WGAL-TV, Pittsburgh Tribune Review, WTAE-TV,
WPVI-TV/6ABC, and Times-Shamrock Newspapers. It may be used in whole or
part, provided any use is attributed to Franklin & Marshall College.