Pollshit
This Washington Post/ABC News/Ipsos poll was conducted among 2,336 respondents, August 9-13, 2024, via the probability-based Ipsos KnowledgePanel®. Results have a margin of sampling error of plus or minus two percentage points for the full sample, including design effects due to weighting. The error margin is plus or minus two points for the sample of 1,975 registered voters; error margins are larger for other subgroups.
Sampling error is not the only cause of differences in polls.
Survey design, management and analysis were provided by Langer Research Associates and The Washington Post. Sampling, field work and data processing were provided by Ipsos Public Affairs.
Unless otherwise noted, trend comparisons are to random-digit-dialed telephone surveys by ABC News and The Washington Post or others. Questions were reformatted as of January 2024 given the change to a self-administered online questionnaire. Differences from previous results may reflect mode effects.
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METHODOLOGICAL DETAILS
This poll was jointly sponsored and funded by The Washington Post, ABC News and Ipsos.
The poll includes a random sample of 2,336 U.S. adults. Interviews were conducted in English and Spanish.
The questionnaire was administered with the exact questions in the exact order as they appear in this document. Demographic questions are not shown. If a question was asked of a reduced base of the sample, a parenthetical preceding the question identifies the group asked. Phrases surrounded by parentheticals within questions indicate clauses that were randomly rotated for respondents.
Ipsos conducted sampling, interviewing and tabulation for the survey using the KnowledgePanel, a representative panel of adults age 18 and over living in the United States. KnowledgePanel members are recruited through probability sampling methods using address-based sampling. Panel members who do not have internet access are provided with a tablet and internet service.
Ipsos used probability-proportional-to-size sampling to draw a national sample of adults using the KnowledgePanel matching U.S. population benchmarks for gender, age, race/ethnicity, education, region, household income, household size, marital status, homeownership status and metropolitan area based on the Census Bureau’s March 2023 Current Population Survey; language dominance based on the Census Bureau’s 2022 American Community Survey; 2020 turnout and vote choice from the 2020 Federal Elections Commission (categories for Biden, Trump, other candidates and non-voters); party identification from 2024 Pew NPORS.
This survey uses statistical weighting procedures to account for deviations in the survey sample from known population characteristics, which helps correct for differential survey participation and random variation in samples. The sample of was weighted to match population estimates for the demographic makeup of U.S. adults, as detailed in the table below.
https://www.washingtonpost.com/documents/a54235f4-501d-4794-b207-cafafcf104f3.pdf