normal distribution


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distribution

 [dis″trĭ-bu´shun]
1. the specific location or arrangement of continuing or successive objects or events in space or time.
2. the extent of a ramifying structure such as an artery or nerve and its branches.
3. the geographical range of an organism or disease.
frequency distribution in statistics, a mathematical function that describes the distribution of measurements on a scale for a specific population.
normal distribution a symmetrical distribution of scores with the majority concentrated around the mean; for example, that representing a large number of independent random events. It is in the shape of a bell-shaped curve. Called also gaussian distribution. See illustration.
 Normal distribution. The approximate percentage of the area (or frequency) lying under the curve between standard deviations is indicated. From Dorland's, 2000.
probability distribution a mathematical function that assigns to each measurable event in a sample group the probability that the event will occur.

nor·mal dis·tri·bu·tion

a specific bell-shaped frequency distribution commonly assumed by statisticians to represent the infinite population of measurements from which a sample has been drawn; characterized by two parameters, the mean (x) and the standard deviation (σ), in the equation:

normal distribution

A bell-shaped frequency distribution of data, the plotted curve of which is symmetrical about the mean, indicating no significant deviation of the data set from the mean.

Properties of a normal distribution
Continuous and symmetrical, with both tails extending to infinity; arithmetic mean, mode, and median are identical. The curve’s shape is completely determined by the mean and standard deviation.

gaus·si·an dis·tri·bu·tion

(gow'sē-ăn dis'tri-byū'shŭn)
The statistical distribution of members of a population around the population mean. In a gaussian distribution, 68.2% of values fall within ± 1 standard deviation (SD); 95.4% fall within ± 2 SD of the mean; and 99.7% fall within ± 3 SD of the mean.
Synonym(s): bell-shaped curve, normal distribution.

normal distribution

Gaussian distribution, a distribution which when expressed graphically is bell-shaped. The distribution to which many frequency distributions of biological variables, such as height, weight, intelligence, etc correspond.

Gauss,

Johann K.F., German physicist, 1777-1855.
gauss - a unit of magnetic field intensity.
gaussian curve - a specific bell-shaped frequency distribution. Synonym(s): gaussian distribution; normal distribution
gaussian distribution - Synonym(s): gaussian curve

nor·mal dis·tri·bu·tion

(nōr'măl dis'tri-byū'shŭn)
Specific bell-shaped frequency distribution commonly assumed by statisticians to represent the infinite population of measurements from which a sample has been drawn.
References in periodicals archive ?
Elandt, "The folded normal distribution: two methods of estimating parameters from moments," Technometrics, vol.
So, the paper proposes the definition of grey degree based on normal distribution.
The first item in (13) and (14) can be calculated using the accumulated probability function of standard normal distribution; the second item cannot be computed by integration.
In previous work [12] it was proved that in the case when the diameter of nanofibres is distributed in compound distribution from several normal distributions, the modal value of the first distribution and the percentage quantity of measurements of the first distribution can be used as a criterion of nanofibres diameter and measurement dispersion estimation.
Generally the normal distribution curve is forcibly fitted to the data and based on that marks are normalised.
When both ([x.sub.i], [y.sub.i]) are known (> LOD), their contribution to the likelihood function ([l.sub.1]) is simply the joint density function of a bivariate normal distribution. That is,
The approach to defining the quantile of free distribution is seen as generalization of the variance-covariance method, in which we assume that the analyzed variables have normal distribution. In this approach we use stable distributions, being the generalization of a normal distribution, but they are characterized by fatter tails than normal distributions.
In the three atypical cases, the initial values of kurtosis of the populations are less than those of the other distributions, and are less than the 3.00 of the normal distribution. In other words, once again, the degree of "heterogeneity of kurtosis," with respect to a normal density, was inherited by the ranks.
5 is shown example of the normal distribution one of these groups.
At a-levels equal to or greater than the p-value, there is evidence that the data do not follow a normal distribution.
"We are not aware of notices from the FDA of drug counterfeiting in the U.S.' normal distribution supply chain since that time," says NACDS.
Requirements include a basic familiarity with statistics in general and normal distribution in particular.