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

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 That range is 793 to 8,498, with a 95 percent confidence interval. Washington Post, "The Health 202: Medicaid expansion in red states is likely to come via voters in November," 4 June 2018 Analysis of the survey data showed a mortality rate of 14.3 deaths per 1,000 people from the period of Sept. 20 to Dec. 31, 2017, yielding a total number of excess deaths at 4,645 people with a confidence interval of 95 percent. Daniel Cusick, Scientific American, "Hurricane Maria Contributed to Nearly 5,000 Deaths, Researchers Say," 30 May 2018 The survey was conducted from March 4 through 18 and has a 3.4 percent margin of error at a 95 percent confidence interval. Joshua Stewart,, "New poll puts Republican John Cox of Rancho Santa Fe in second place in governor's race," 22 Mar. 2018 HQuack creator Jake Mor told Ars the site started as a simple program on his computer, Googling questions and giving confidence intervals to the possible answers based on the number of results. Kyle Orland, Ars Technica, "A wave of cheating AI robots is threatening to ruin HQ Trivia [Updated]," 12 Feb. 2018 The survey, which was conducted Oct. 9 through Oct. 12, has a 4.4 percentage point margin of error and 95 percent confidence interval. Andrea Zelinski, Houston Chronicle, "Democratic pollster suggests tight race for AG," 14 Dec. 2017

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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Last Updated

25 Sep 2019

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The first known use of confidence interval was in 1934

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