# standard deviation

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Related to standard deviation: variance

## deviation

[de″ve-a´shun]
1. a turning away from the regular standard or course.
2. in ophthalmology, strabismus.
3. in statistics, the difference between a sample value and the mean.
axis deviation an axis shift in the frontal plane, as seen on an electrocardiogram. There are three types: Left, from −30° to −90°; Right, from +90° to +180°; and Undetermined, which may be either extreme left or extreme right, from −90° to +180°.
conjugate deviation dysfunction of the ocular muscles causing the two eyes to diverge to the same side when at rest.
sexual deviation sexual behavior or fantasy outside that which is morally, biologically, or legally sanctioned, often specifically one of the paraphilias.
standard deviation (SD) the dispersion of a random variable; a measure of the amount by which each value deviates from the mean. It is equal to the square root of the variance. For data that have a normal distribution, about 68 per cent of the data points fall within (plus or minus) one standard deviation from the mean and about 95 per cent fall within (plus or minus) two standard deviations. Symbol σ.
ulnar deviation a hand deformity, seen in chronic rheumatoid arthritis and lupus erythematosus, in which swelling of the metacarpophalangeal joints causes the fingers to become displaced to the ulnar side. Called also ulnar drift. See illustration. Ulnar deviation (ulnar drift) of the metacarpophalangeal joint, a characteristic sign of rheumatoid arthritis. From Pedretti and Early, 2001.

## stan·dard de·vi·a·tion (SD, σ),

1. statistical index of the degree of deviation from central tendency, namely, of the variability within a distribution; the square root of the average of the squared deviations from the mean.
2. a measure of dispersion or variation used to describe a characteristic of a frequency distribution.

## standard deviation

A statistical term that indicates the relative variability of a value around its mean; the square root of variance.

## standard deviation

Square root of the variance Statistics The most widely used measure of the dispersion of a set of values about a mean, which is equal to the positive square root of the variance, where a graphic representation of the data points is described by a curve with Gaussian distribution–GD–ie, bell-shaped. See Gaussian curve.

## stan·dard de·vi·a·tion

(σ, SD) (stan'dărd dē'vē-ā'shŭn)
1. Statistical index of the degree of deviation from central tendency, namely, of the variability within a distribution; the square root of the average of the squared deviations from the mean.
2. A measure of dispersion or variation used to describe a characteristic of a frequency distribution.

## standard deviation

A measure of dispersion widely used in statistics. Standard deviation is the square root of the arithmetic average of the squares of the deviations of the members of a sample from the mean.

## standard deviation (S)

a measure of the variation in a sample, calculated as the square root of the VARIANCE. Mean values are often followed by the standard deviation.see STANDARD ERROR.

## Standard deviation

A measure of the distribution of scores around the average (mean). In a normal distribution, two standard deviations above and below the mean includes about 95% of all samples.

## stan·dard de·vi·a·tion

(SD) (stan'dărd dē'vē-ā'shŭn)
1. Statistical index of degree of deviation from central tendency, namely, of variability within a distribution; square root of average of squared deviations from mean.
2. Measure of dispersion or variation used to describe a characteristic of a frequency distribution.
References in periodicals archive ?
In our study, mean and standard deviation of total cholesterol (in mg/dl) of A blood group is 155.30 [+ or -] 21.13 and for B blood group is 185.75 [+ or -] 31.16, and for AB blood group 198.50 [+ or -] 41.49, and O blood group is 175.71 [+ or -] 23.32.
It is also obvious from this table that in CE construct, attitude of the rural area respondents is little positive with mean value 3.65 than that of the urban area value 3.39, and results of the standard deviation are of its vice versa.
Mean and standard deviation of birth weights in babies born by normal delivery were 3.065 and 0.2928 respectively and in babies born by CS were 2.9311 and 0.3796 respectively.
The average wetted depth of inline is 13.68 cm with standard deviation of 0.17 cm and the coefficient of variation is 1.22 % and the average witted depth of online is 13.74 cm with standard deviation of 0.12 cm and the coefficient of variation is 0.85 %.
For input signal of SNR higher than a certain value (25 dB for 8192 samples in series), the standard deviation of measurement reaches a minimum, constant value.
As shown in Figure 3, nonsegregated areas have a lower standard deviation in comparison with segregated areas.
The bullet has a leisurely 1,058 fps muzzle velocity from the Anschutz rifle and didn't quite keep the low extreme spread and standard deviation seen on other premium match loads.
The average mean for the statement was 3.28 with the standard deviation of 1.53.
Consider a second appraisal with a market value estimate of \$ 1,000,000 and a standard deviation of \$200,000 as illustrated in Figure 4.
They used the Chiras and Manaster (1978) weighted implied standard deviation method to forecast the expected volatility of underlying asset to calculate the theoretical price of an option.
Worse, standard deviation's relevance depends on the location of the mean.
dollar GDP deflator at historical average minus one standard deviation in 2014-15###20###20###20###19###18###17###15###12

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