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Winthrop/ETV Poll

Methodology - October 2008 Poll

The data represent responses from 2026 individual likely voters from South Carolina, North Carolina and Virginia gathered between September 28 and October 19, 2008. These include:

617 respondents from SC (margin of error +/- 3.94% at the 95% confidence level)

744 respondents from NC (margin of error +/- 3.59% at the 95% confidence level)

665 respondents from VA (margin of error +/- 3.8% at the 95% confidence level)

As is true with all survey data, any results that use a subset of the respondents will have a higher margin of error. For the purpose of these results, "Working Class" is defined as a respondent who reported $50,000 or less total annual household income.

Questions Regarding Length of Time in Field
While this is a long time for a political survey to be in the field, we feel it does two things:

Increase the "representativeness" of the sample without weighting

Smoothes the erratic jumps and dips seen when overnight polls are aggregated

First, most polls done in a few days call during the daytime and must use a complicated weighting scheme for the data. For example, retirees and stay-at-home moms are more likely to be reached during the day and this over-sampling must be accounted for in the final results. The Social & Behavioral Research Lab (SBRL) at Winthrop University calls only on weekday evenings, and during the day and evenings on weekends. This allows respondents to be randomly sampled in their proper proportions without additional weighting. Further, with polls in the field for only a few days, truly randomly selected respondents are rarely called back if they are not reached on the first try. Staying in the field longer allows for multiple attempts--a method that mirrors better sampling procedures.

While the trade off between speed of data gathering and un-weighted accuracy of the sample is unacceptable to some, un-weighted sample quality holds a supreme position for us since this data will be used for academic research after the conclusion of the election.

Second, a longer time in the field has a "smoothing effect" on the data. Trends are more fluid compared to the choppy ups and downs seen in many quick snapshot polls. However, spending too long in the field can mask significant shifts. The consumer of this data should use these results to paint a fuller picture of trends seen from the multitude of quick snapshot polls; she or he should not assume these results supplant any other methodologically sound data.

Questions regarding the definition of "Likely Voter"
Respondents were randomly selected from lists of registered voters in each state. The interviewer asked for the selected registered voter by name and then verbally confirmed their name and current registration status. After determining that we had the correct individual and that they were, in fact, still registered in the state where they lived (and were called), we screened the respondents using an additional question to determine likelihood of voting. Only those currently registered voters who responded that they "definitely plan to vote in the November presidential election" are included in these results. Some polls use Random Digit Dialing and then apply a series of questions to determine likelihood of voting. These questions may include whether the individual is registered (we already know our respondents are registered because they are pulled from lists of registered voters), interest in the outcome of the election, how closely they have followed the election, how often they have voted in the past, and others. We are concerned that any method that screens for, or more heavily weights, the responses of those who have previously voted will under-represent newly registered voters. While in most elections, newly registered voters make up so few of the electorate as to make this concern unwarranted, we believe that newly registered voters may play a pivotal role in the presidential election of 2008 and we chose a methodology that would ensure their inclusion.

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SCETV Webmaster
E-mail: webmaster@scetv.org For more information about Winthrop/ETV Poll, contact:

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E-mail: acrouch@scetv.org

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Rob Schaller, Director of Communications
E-mail: rschaller@scetv.org

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