confidence interval


Definition of confidence interval

: a group of continuous or discrete adjacent values that is used to estimate a statistical parameter (such as a mean or variance) and that tends to include the true value of the parameter a predetermined proportion of the time if the process of finding the group of values is repeated a number of times

Examples of confidence interval in a Sentence

Recent Examples on the Web The study initially planned to survey 500 individuals, but Flanagan said enough households and neighborhoods were surveyed to get a 95% confidence interval. Stephanie Innes, The Arizona Republic, "Study finds more than 1 in 10 Maricopa County residents has been infected with COVID-19," 16 Nov. 2020 The smaller the confidence interval, the more sure that researchers are about a number. Adam Rogers, Wired, "We’ll Need More Than One Vaccine to Beat the Pandemic," 13 Nov. 2020 The confidence interval for the active cases ranges from 0.1% to 2%. cleveland, "Gov. Mike DeWine says Ohioans will wear masks for awhile, after new study finds just 1.5% of state had coronavirus antibodies in July," 1 Oct. 2020 Britain’s Office for National Statistics (ONS) has mulled introducing confidence intervals for its estimates—but no one knows quite how wide the bands should be. The Economist, "Crisis measures The pandemic could lead statisticians to change how they estimate GDP," 30 May 2020 The confidence intervals are wide, ranging from 2,700 to 50,000, but the numbers go up if a wider radius around the plant is used. John Timmer, Ars Technica, "Ditching coal in the US is saving lives, helping crops," 6 Jan. 2020 According to Live Science, the team reached its conclusion with a standard deviation of 3.5 sigma, far below the 5 sigma confidence interval that physicists rely on in order to confirm a theory. Jennifer Leman, Popular Mechanics, "New Research Suggests the Universe May Be a Giant Loop," 5 Nov. 2019 In some cases, the confidence interval ranges from negative infinity to positive infinity: literally any effect size is possible, and the researchers can’t reject the possibility that the program either paid for itself or was actively destructive. Dylan Matthews, Vox, "Government programs usually cost money. These ones actually make money.," 30 July 2019 The lower side of 95 percent confidence interval has global population peaking in 2070 and falling slowly from there; the upper side has population approaching 13 billion and still increasing in 2100. Kelsey Piper, Vox, "We’ve worried about overpopulation for centuries. And we’ve always been wrong.," 20 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'confidence interval.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of confidence interval

1934, in the meaning defined above

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The first known use of confidence interval was in 1934

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Last Updated

19 Nov 2020

Cite this Entry

“Confidence interval.” Dictionary, Merriam-Webster, Accessed 23 Nov. 2020.

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