confidence interval

American  

[kon-fi-duhns in-ter-vuhl] / ˈkɒn fɪ dəns ˌɪn tər vəl /

noun

Statistics.

1. a range of values above and below a given statistic, with a specified probability that the true value falls within that range: the span of the interval is equal to twice the margin of error.

   An overview of 20 studies revealed that calcium supplements reduced the risk of total fracture, showing a relative risk of 0.89 with a 95% confidence interval of 0.81 to 0.96.

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confidence interval British  

noun

1. statistics an interval of values bounded by confidence limits within which the true value of a population parameter is stated to lie with a specified probability

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Etymology

Origin of confidence interval

First recorded in 1930–35

Example Sentences

This is done by calculating a "confidence interval," which, in the simplest case, can be found by repeating an experiment many times and seeing how the results vary.

From Science Daily • Nov. 9, 2023

While letting its topline numbers for the city and county stand without qualification, LAHSA’s report provided a confidence interval for the total count in its administrative area covering all of L.A.

From Los Angeles Times • Jun. 29, 2023

But because the lower bound of the confidence interval around this figure fell below FDA’s required 20%, it didn’t meet the agency’s efficacy standard for preventing less severe disease.

From Science Magazine • May 18, 2023

The survey was conducted in January among a nationally representative sample of 2,000 adults, providing an estimated maximum sampling error of about plus or minus 2 percentage points at a 95% confidence interval, organizers said.

From Washington Times • May 10, 2023

When the random sample selected contains one thousand people, the theoretical 95 percent confidence interval for estimating the percentage who favor candidate X or dog food Y is about plus or minus 3 percent.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos