The survey of the United States was conducted by Zogby International, a world-renowned polling firm based in Utica, New York. Zogby International surveys employ sampling strategies in which selection probabilities are proportional to population size within area codes and exchanges. Up to ten 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. Zogby International’s sampling and weighting procedures also have been validated through its political polling: more than 95% of the firm’s polls have come within 1% of actual election-day outcomes. The sample compositions are as follows:
- General Public: The survey was conducted between August 20 and September 4, 2007 through telephone interviews with a nationwide, statistically representative general population sample consisting of 1,200 American adults (18 years of age and older). Weighting by region, party, age, race, religion, gender is used to adjust for non-response. The margin of error is plus or minus 2.9 percentage points.
- Opinion Leaders: The survey was conducted between August 20 and September 19, 2007 through telephone interviews with a sample of 200 opinion elites nationwide. The sample represents influential leaders from the media (25%), academia (25%), NGOs (25%), and public sector (25%). Within each grouping, respondents were randomly selected from Zogby International’s proprietary, public, and purchased lists, and were screened for familiarity with U.S-China relations. The margin of error is plus or minus 7.1 percentage points.
- Business Leaders: The survey was conducted between August 20 and September 14, 2007 through telephone interviews with a sample of 150 business elites nationwide. The sample was based on executives and senior level decision makers from a cross-section of American corporations with over 500 employees, and was also randomly drawn from trade associations, trade groups, lobby firms, chambers of commerce and economic development groups. The margin of error is plus or minus 8.2 percentage points.
- Congressional Staffers: The survey was conducted between August 20 and September 14, 2007 through telephone interviews and interactive interviews with a sample of 100 Congressional staffers. The sample was comprised of randomly selected senior staff, including legislative counsels, legislative directors, legislative assistants, chiefs of staffs and senior advisors from purchased Congressional staff email and telephone lists. Slight weights were added to responses to simulate the exact balance of the overall composition of the current Congress. The margin of error is plus or minus 10 percentage points.