The survey findings presented in this release are based on the results of interviews conducted September 19 - 25, 2022. The interviews were conducted at the Center for Opinion Research at Franklin & Marshall. The data included in this release represent the responses of 517 registered Pennsylvania voters, including 235 Democrats, 210 Republicans, and 72 independents.[i] The sample of voters was obtained from Marketing Systems Group. All sampled respondents were notified by mail about the survey. Interviews were completed over the phone and online depending on each respondent’s preference. Survey results were weighted (age, gender, education, geography, vote history, and party registration) using an iterative weighting algorithm to reflect the known distribution of those characteristics. Estimates for age, geography, and party registration are based on active voters within the PA Department of State’s voter registration data. Gender and education is estimated using data from the November 2018 CPS Voter Registration Supplement.[ii]
The sample error for this survey is +/- 5.6 percentage points when the design effects from weighting are considered. An alternative means of calculating the variation in a sample is to take a series of bootstrap samples from the original sample and to use those bootstrapped samples to produce an estimate of sampling error.[iii] The procedure involves resampling a data set, calculating a statistic for each bootstrapped sample, accumulating the results of these samples and calculating a sample distribution. The standard deviation of the mean of 10,000 bootstrapped samples for the estimated positive job approval for President Biden was 2.0% and 95% of the samples fell within a range of 25% and 33%.