February 5, 2016

Most Americans Say Government Doesn’t Do Enough to Help Middle Class

Methodology

The analysis in this report is based on two telephone surveys conducted December 8-13, 2015 and January 7-14, 2016. A combination of landline and cell phone random digit dial samples were used; both samples were provided by Survey Sampling International. Interviews were conducted in English and Spanish. Respondents in the landline sample were selected by randomly asking for the youngest adult male or female who is now at home. Interviews in the cell sample were conducted with the person who answered the phone, if that person was an adult 18 years of age or older. For detailed information about our survey methodology, see http://www.pewresearch.org/methodology/u-s-survey-research/

The survey conducted December 8-13, 2015 was among a national sample of 1,500 adults, 18 years of age or older, living in all 50 U.S. states and the District of Columbia (525 respondents were interviewed on a landline telephone, and 975 were interviewed on a cell phone, including 582 who had no landline telephone). The survey was conducted by interviewers at Princeton Data Source under the direction of Princeton Survey Research Associates International.

The survey conducted January 7-14, 2016 was among a national sample of 2,009 adults, 18 years of age or older, living in all 50 U.S. states and the District of Columbia (504 respondents were interviewed on a landline telephone, and 1,505 were interviewed on a cell phone, including 867 who had no landline telephone). The survey was conducted under the direction of Abt SRBI.

The combined landline and cell phone sample are weighted using an iterative technique that matches gender, age, education, race, Hispanic origin and nativity and region to parameters from the 2014 Census Bureau’s American Community Survey (for the January 2016 survey) and the 2013 Census Bureau’s American Community Survey (for the December 2015 survey) and population density to parameters from the Decennial Census. The sample also is weighted to match current patterns of telephone status (landline only, cell phone only, or both landline and cell phone), based on extrapolations from the 2015 National Health Interview Survey (for the January 2016 survey) and the 2014 National Health Interview Survey (for the December 2015 survey). The weighting procedure also accounts for the fact that respondents with both landline and cell phones have a greater probability of being included in the combined sample and adjusts for household size among respondents with a landline phone. The margins of error reported and statistical tests of significance are adjusted to account for the survey’s design effect, a measure of how much efficiency is lost from the weighting procedures.

The following table shows the unweighted sample sizes and the error attributable to sampling that would be expected at the 95% level of confidence for different groups in the January 2016 survey:

The following table shows the unweighted sample sizes and the error attributable to sampling that would be expected at the 95% level of confidence for different groups in the December 2015 survey:

Sample sizes and sampling errors for other subgroups are available upon request.

In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of opinion polls.