normal distribution


Definition of normal distribution

: a probability density function that approximates the distribution of many random variables (such as the proportion of outcomes of a particular kind in a large number of independent repetitions of an experiment in which the probabilities remain constant from trial to trial) and that has the form {latex}f(x) = \frac{1}{\sqrt{2\pi\sigma^{2}}}e^{-\frac{(x - \mu)^{2}}{2\sigma^{2}}}{/latex} where μ is the mean and σ is the standard deviation — compare normal curve

Examples of normal distribution in a Sentence

Recent Examples on the Web One consequence of this is that the normal distribution, or bell curve, which says Black Swan events are highly unlikely to happen, no longer holds true. Jemma Green, Forbes, 4 Aug. 2022 Robert Rohde, a climate scientist at Berkeley Earth, prepared the chart below, showing Tuesday’s 104.4 degrees (40.2 Celsius) far, far off the normal distribution: A normal summer high temperature near London is about 20-25 °C (68-77 °F). Jacob Feuerstein, Washington Post, 20 July 2022 The question is not whether a sum of small, independent values would be likely to follow a normal distribution. Jessica Riskin, The New York Review of Books, 21 Apr. 2022 Launching in Singapore and getting to 12 countries would be the normal distribution area for Pixel phones. Ron Amadeo, Ars Technica, 3 Feb. 2022 But this is no longer the case: Instead of a normal distribution, now the distribution of voters is more barbelled, with a hollow center and the center of gravity for each party far from the center of the other. Noah Millman, The Week, 12 Oct. 2021 Thinking back to statistics class, remember the normal distribution curve where most people scored in the middle and there were some outliers who performed really badly and others who excelled and got more than 98%? Nida Leardprasopsuk, Forbes, 13 Oct. 2021 As seen in the NASA illustration below of a normal distribution of temperatures, or bell curve, as the average temperature of the planet warms, the curve shifts right. Jeff Berardelli, CBS News, 14 June 2021 Picture a bell curve—the graph that illustrates a normal distribution, with most of the data congregating at the center, with long tails at the high and low ends. Caroline Delbert, Popular Mechanics, 14 June 2021 See More

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

First Known Use of normal distribution

1897, in the meaning defined above

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The first known use of normal distribution was in 1897

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Dictionary Entries Near normal distribution

normal dispersion

normal distribution

normal divisor

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Statistics for normal distribution

Last Updated

11 Aug 2022

Cite this Entry

“Normal distribution.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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