Question:

Poll Demographics

About this Poll


TCPalm.com/Zogby poll methodology

Survey Methodology Florida Likely Voters Sept. 27, 2010 through Sept. 29, 2010

Zogby International was commissioned to conduct a telephone survey of Florida Likely Voters.

The target sample is 600 interviews with approximately 26 questions asked. Samples are randomly drawn from telephone CDs of national listed sample. Zogby International surveys employ sampling strategies in which selection probabilities are proportional to population size within area codes and exchanges. Up to six calls are made to reach a sampled phone number. Cooperation rates are calculated using one of AAPOR’s approved methodologies and are comparable to other professional public-opinion surveys conducted using similar sampling strategies. Weighting by region, party, age, race and gender are used to adjust for non-response. The margin of error is +/- 3.5 percentage points. Margins of error are higher in sub-groups. The MOE calculation is for sampling error only.

SAMPLING

The majority of telephone lists for polls and surveys are produced in the IT department at Zogby International. Vendor-supplied lists are used for regions with complicated specifications, e.g., some Congressional Districts. Customer-supplied lists are used for special projects like customer satisfaction surveys and organization membership surveys.

Telephone lists generated in our IT department are called from a nationally published set of phone CDs of listed households, ordered by telephone number. Residential (or business) addresses are selected and then coded by region, where applicable. An appropriate replicate1 is generated from this parent list, applying the replicate algorithm repeatedly with a very large parent list, e.g., all of the US.

Acquired lists are tested for duplicates, coded for region, tested for regional coverage, and ordered by telephone, as needed.

The resulting list is loaded into the CATI application and the randomize function within the CATI software is run to further assure a good mix for the telephone list.

INTERVIEWING

Interviews are conducted at Zogby International by professional interviewers trained on our computer-assisted telephone interviewing (CATI) computer system. A policy requiring one supervisor to no more than twelve interviewers is used. The sample management module of the CATI system gives all prospective respondent households in the source telephone list the same chance of joining the sample. Regional quotas are employed to ensure adequate coverage nationwide.

WEIGHTING

Reported frequencies and crosstabs are weighted using the appropriate demographic profile to provide a sample that best represents the targeted population from which the sample is drawn. The proportions comprising the demographic profile are compiled from historical exit poll data, census data, and from Zogby International survey data.

SAMPLING ERROR

Sampling Error, often referred to as the Margin of Error, is the percentage that survey results are likely to differ from the actual due to the size of the sample drawn. If a survey were conducted of all the members of a population, the sampling error would be zero. There are other sources of possible error in survey research such as sample design error and measurement error.