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.
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Why Pew Research Center will display margins of error in some graphics
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Why do some open-ended survey questions result in higher item nonresponse rates than others?
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Validating 2020 voters in Pew Research Center’s survey data
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How keyword oversampling can help with text analysis
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How many Taiwanese live in the U.S.? It’s not an easy question to answer
Surveys can produce widely different estimates depending on how people are asked about their backgrounds.
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Using cognitive interviewing to design survey questions about democracy
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Developing survey questions on sensitive topics in India
Asking balanced questions required investing considerable time and effort into developing and testing the questionnaire.
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‘What’s the difference between income and wealth?’ and other common questions about economic concepts
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