For our Summer 2016 survey:
The Marketplace Edison Research Survey is a national survey of Americans ages 18 years and older. A total of 1,022 respondents were interviewed with 501 interviews conducted by telephone and 521 interviews conducted online. Among the telephone interviews, 301 were conducted via a landline phone and 200 interviews conducted via a cell phone so that we could achieve the proper proportion of coverage of households in the United States that do not have a landline phone. The landline and cell phone sample of phone numbers and the email addresses for the online survey were provided by Survey Sampling International (SSI).
The average length of the telephone interviews was sixteen minutes. The telephone interviews were conducted from May 18th – 24th, 2016.
The data was weighted to match the most recent United States population estimates from the U.S. Census Bureau for age, gender, race and region of the country.
With a total sample size of 1,022 respondents, the calculated margin of error with a 95% confidence interval for results among the entire sample is +/- 3%.
The calculated margins of error for results among smaller sub-groups are higher.
For our Winter 2016 survey:
The Marketplace Edison Research Survey is a national survey of Americans ages 18 years and older. A total of 1,012 respondents were interviewed with 501 interviews conducted by telephone and 512 interviews conducted online. Among the telephone interviews, 300 were conducted via a landline phone and 201 interviews conducted via a cell phone so that we could achieve the proper proportion of coverage of households in the United States that do not have a landline phone. The landline and cell phone sample of phone numbers and the email addresses for the online survey were provided by Survey Sampling International (SSI).
The average length of the telephone interviews was fourteen minutes. The telephone interviews were conducted from February 8th to 17th, 2016.
The data was weighted to match the most recent United States population estimates from the U.S. Census Bureau for age, gender, race and region of the country.
With a total sample size of 1,012 respondents, the calculated margin of error with a 95% confidence interval for results among the entire sample is +/- 3%. The calculated margins of error for results among smaller sub-groups are higher.
The February wave of data is tracked with a previous wave, conducted September 8th to 18th, 2015, in which a total of 1,016 respondents were interviewed (501 conducted by telephone, 515 conducted online). The calculated margin of error for the September wave of data is also +/- 3% among the entire sample.