Definitions for standard deviation
stan·dard devi·a·tion

Princeton's WordNetRate this definition:0.0 / 0 votes

1. standard deviationnoun

   the square root of the variance

WiktionaryRate this definition:0.0 / 0 votes

1. standard deviationnoun

   A measure of how spread out data values are around the mean, defined as the square root of the variance.

WikidataRate this definition:2.0 / 1 vote

1. Standard deviation

   In statistics and probability theory, standard deviation shows how much variation or dispersion exists from the average, or expected value. A low standard deviation indicates that the data points tend to be very close to the mean; high standard deviation indicates that the data points are spread out over a large range of values. The standard deviation of a random variable, statistical population, data set, or probability distribution is the square root of its variance. It is algebraically simpler though practically less robust than the average absolute deviation. A useful property of standard deviation is that, unlike variance, it is expressed in the same units as the data. Note, however, that for measurements with percentage as the unit, the standard deviation will have percentage points as the unit. In addition to expressing the variability of a population, standard deviation is commonly used to measure confidence in statistical conclusions. For example, the margin of error in polling data is determined by calculating the expected standard deviation in the results if the same poll were to be conducted multiple times. The reported margin of error is typically about twice the standard deviation ­– the radius of a 95 percent confidence interval. In science, researchers commonly report the standard deviation of experimental data, and only effects that fall far outside the range of standard deviation are considered statistically significant – normal random error or variation in the measurements is in this way distinguished from causal variation. Standard deviation is also important in finance, where the standard deviation on the rate of return on an investment is a measure of the volatility of the investment.

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1. standard deviation

   The standard deviation symbol -- In this Symbols.com article you will learn about the meaning of the standard deviation symbol and its characteristic.

Matched Categories

1. • Statistics
   • Variance

How to pronounce standard deviation?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

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   Indian

   Priya

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   Neerja

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   Oliver

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   South African

How to say standard deviation in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of standard deviation in Chaldean Numerology is: 4

2. Pythagorean Numerology

   The numerical value of standard deviation in Pythagorean Numerology is: 9

Examples of standard deviation in a Sentence

1. Cobb Scott:

   We looked at everything from learning and memory to different aspects of executive functioning such as abstraction ability, and we basically showed that the largest effects -- which was around a third of a standard deviation -- was in the learning of new information and some aspects of executive functioning, memory and speed of processing.

2. Cobb Scott:

   It surprised, I think, all of us doing this analysis that the effects were not bigger than we found, but I would say that the clinical significance of a quarter of a standard deviation is somewhat questionable.

References

1. ^ Princeton's WordNet
   http://wordnetweb.princeton.edu/perl/webwn?s=standard deviation
2. ^ Wiktionary
   https://en.wiktionary.org/wiki/Standard_Deviation
3. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=standard deviation