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.
Latest from Decoded
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Q&A: How Pew Research Center surveyed nearly 30,000 people in India
To represent the views of Indians from a wide range of backgrounds, we fielded our largest-ever single-country survey outside the U.S.
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Measuring caste in India
Despite the caste system’s significance in India, there is no consensus on what proportion of Indians belong to each caste category.
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Estimating U.S. newspaper circulation is a challenge — especially for 2020
Using data from outside organizations has some advantages, but also poses challenges, especially when it comes to media industry data.
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Improving the way we categorize family income
We’ve made adjustments to account for differences in purchasing power by survey respondents’ household size and geography.
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Examining how survey mode affects Americans’ views of international affairs
Responses to survey questions asked online can differ from those asked on the phone.
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The impact of survey mode on measuring public opinion in Italy
Using a “bridge survey,” we simultaneously fielded identical questions and response options via both in-person and telephone interviews.
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What different survey modes and question types can tell us about Americans’ views of China
Regardless of mode or measure, most Americans have a negative view of China – and opinions have become more unfavorable in recent years.
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Contending with the 80/20 rule when studying online behavior
The Pareto principle, or “80/20 rule,” holds that in many systems, a minority of cases produce the majority of outcomes.
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Assessing the consistency of online opt-in polls
In this post, we examine whether online opt-in or “nonprobability” surveys are consistent in the same ways as probability-based surveys.
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How quantitative methods can supplement a qualitative approach when working with focus groups
In a recent project involving focus groups, we tested out quantitative as well as qualitative research methods.
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