Understanding error bars in charts
Error bars illustrate the margin of error for a survey estimate by showing how precise that estimate is. Here are some answers to common questions that might help you better understand charts with error bars.
A behind-the-scenes blog about research methods at Pew Research Center.
For our latest findings, visit pewresearch.org.
Survey Methods
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Why and how we’re weighting surveys for past presidential vote
This piece explains why, when and how we are weighting our surveys on Americans’ past vote.
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Validating 2022 voters in Pew Research Center’s survey data
Knowing who voted is critical to developing an accurate understanding of an election’s outcome.
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Measuring partisanship in Europe: How online survey questions compare with phone polls
We compared three different online survey methods in certain countries to see which one would most closely replicate our phone results.
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How adding a ‘Don’t know’ response option can affect cross-national survey results
In our surveys, people are much less likely to skip questions online than when speaking to interviewers in person or on the phone; we explore how offering a “Don’t know” option in online surveys affects results.
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Assessing the effects of generation using age-period-cohort analysis
In this piece, we demonstrate how to conduct age-period-cohort analysis, a statistical tool, to determine the effects of generation.
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Can machines compete with humans in transcribing audio? A case study using sermons from U.S. religious services
To test whether machine transcription would be practical for studies of sermons in 2019 and 2020, we compared human and machine transcriptions of snippets from a random sample of 200 audio and video sermons.
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Identifying partisan ‘leaners’ in cross-national surveys
In 2022, we experimented with a new question in cross-national surveys to capture the international equivalent of U.S. partisan “leaners.”
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Nonresponse rates on open-ended survey questions vary by demographic group, other factors
Demographic characteristics and other factors, such as the devices that respondents use to take surveys, are tied to Americans’ willingness to engage with open-ended questions.
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Testing survey questions about a hypothetical military conflict between China and Taiwan
Given the complexities of geopolitics, how might wording affect responses to a question about a hypothetical conflict between China and Taiwan?
