standard deviation

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Related to Std dev: 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 ?
(3a) CASH FLOW =a + [b.sub.1](BOARD QUALITY) + [b.sub.2](CORPORATE CULTURE) + [b.sub.3](MANAGERIAL INCENTIVES) + [b.sub.4](REGULATORY ISSUES) + [b.sub.5](ASSETS) + [b.sub.6](AGE) + [b.sub.7](BROKERAGE AVAILABILITY) + [b.sub.8](DEFERRED LOAD) + [b.sub.9](EXPENSE RATIO) + [b.sub.10](FRONT END LOAD) + [b.sub.11](FUND FAMILY) + [b.sub.12](FUND FOCUS) + [b.sub.13](EARNINGS GROWTH) + [b.sub.14](INSTITUTIONAL) + [b.sub.15](STOCK) + [b.sub.16](STD DEV) + [b.sub.17](TOTAL RETURN) + [b.sub.18](TURNOVER RATIO) + [b.sub.19](12B-1 PLAN) + e
(3b) CASH FLOW =a + [b.sub.1](STEWARDSHIP GRADE) + [b.sub.2](ASSETS) + [b.sub.3](AGE) + [b.sub.4](BROKERAGE AVAILABILITY) + [b.sub.5](DEFERRED LOAD) + [b.sub.6](EXPENSE RATIO) + [b.sub.7](FRONT END LOAD) + [b.sub.8](FUND FAMILY) + [b.sub.9](FUND FOCUS) + [b.sub.10](EARNINGS GROWTH) + [b.sub.11](INSTITUTIONAL) + [b.sub.12](STOCK) + [b.sub.13](STD DEV) + [b.sub.14](TOTAL RETURN) + [b.sub.15](TURNOVER RATIO) + [b.sub.16](12B-1 PLAN) + e
STD DEV: The three-year annualized standard deviation of the fund's return
The % CONTAM* STD DEV [P.sub.c]* MEAN SHIFT interaction has a b-weight of .0202.
The N*STD DEV [P.sub.c] *MEAN SHIFT can be interpreted to mean that when the MEAN SHIFT is zero, increases in the STD DEV [P.sub.c] do not have an effect on Type I error rates as the sample size decreases.
Variable b-weight Standard Error Constant .0541 .00095 MEAN SHIFT -.0018 .00046 STD DEV [P.sub.c] -.0011 .00045 % CONTAM -.0241 .00918 N -.00006 .00001 N*STD DEV [P.sub.c] .000025 .000006 N*% CONTAM .00053 .00012 N*MEAN SHIFT .000036 .000006 STD DEV [P.sub.c]* % CONTAM -.0081 .0043 STD DEV [P.sub.c]*MEAN SHIFT .00048 .00021 % CONTAM*MEAN SHIFT .0292 .0042 % CONTAM*STD DEV [P.sub.c]*MEAN SHIFT .0202 .0018 N*STD DEV [P.sub.c] *MEAN SHIFT -.000016 .000002 N*% CONTAM * MEAN SHIFT -.0005 .00004 Table 5.
The moisture observations have advertised reproducibility (std dev differences between twin soundings) of 2% and a total uncertainty in a sounding for reports with T > -60[degrees]C of 5% (2-sigma confidence level of cumulative effects, including repeatability, long-term stability, measurement conditions, and measurement electronics, as well as dynamic effects including response time).
Overall, the WVSS dataset matchups reveal a systematic difference (bias) of 0.15 g [kg.sup.-1] and a random difference (std dev) of 0.62 g [kg.sup.-1].
SH data from descending aircraft showed a slightly smaller bias (+0.02 g [kg.sup.-1]) and larger random difference (std dev of 0.69 g [kg.sup.-1]) when compared with +0.20 g [kg.sup.-1] bias and 0.54 g [kg.sup.-1] std dev for ascending reports.
Random differences in the ascent data remain fairly consistent for environments below 50% RH, with std dev near 0.5 g [kg.sup.-1], but approach 1.1 g [kg.sup.-1] in environments between 50% and 85% RH, and then return to 0.5 g [kg.sup.-1] in the highest RH ranges.
The best agreements appear in the lowest 50 hPa, with random differences (std dev) on the order of 0.5 g [kg.sup.-1] and biases varying between -0.3 and +0.3 g [kg.sup.-1].