distribution

distribution /dis·tri·bu·tion/ (dis?tri-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.

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chi-square distribution  a distribution of sample differences using observations of a random sample drawn from a normal population.

normal distribution  a continuous probability density function roughly characterizing a random variable that is the sum of a large number of independent random events; usually represented by a smooth bell-shaped curve symmetric about the mean.

Normal distribution. The approximate percentage of the area (or frequency) lying under the curve between standard deviations is indicated.

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dis·tri·bu·tion (dstr-byshn)

n.

1. The extension of the branches of arteries or nerves to the tissues and organs.

2. The area in which the branches of an artery or a nerve terminate, or the area supplied by such an artery or nerve.

3. A set of numbers and their frequency of occurrence from measurements within a statistical population.

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distri·bution·al adj.

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distribution

the arrangement of numerical data. The arrangement may be in accordance with magnitude, a frequency distribution, or in relation to geographical location, a spatial distribution.

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age distribution

see age distribution.

bimodal distribution

the distribution has two regions of high frequency of observations separated by a zone of low frequency.

binomial distribution

a probability distribution associated with two mutually exclusive outcomes.

cluster distribution

a nonrandom distribution with observations aggregating about geographic or temporal variables. May be deceptive and merely reflect the distribution of an uneven population.

frequency distribution

a table or graph of the frequency of occurrence of each value of a variable.

Gaussian distribution

see normal distribution (below).

hypergeometric distribution

may apply to sampling without replacement of a finite population.

lognormal distribution

a distribution which is normal when the log values of the variable are considered.

normal distribution

a graph of the distribution appears as a bell-shaped curve which is symmetrical on the two sides of the vertical axis through the peak of the curve. Called also gaussian distribution.

parent distribution

the distribution (population) that was originally sampled.

Poisson distribution

see poisson distribution.

regular distribution

distributed at regular intervals of time or space; all values within its given interval are equally likely.

sex distribution

an increase in frequency in one sex, which includes neutered males and neutered females. Called also sex-linked or sex-associated.

skewed distribution

a distribution in which the curve illustrating it is not symmetrical but has a long tail on one or other side of the graph.

spatial distribution

variations in distribution related to position in space, e.g. close to the door of a barn.

t-distribution

see t-test.

temporal distribution

variation in distribution related to time, e.g. occurrence of disease incidents after visits by veterinarians, inseminators, feed salesmen.

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distribution Clinical medicine The pattern of involvement of a tissue by a particular condition. See Batwing distribution, Fat distribution, Mocassin distribution, Stocking & glove distribution Epidemiology The frequency and pattern of health-related characteristics and events in a population Pharmacology The location–eg intravascular or extravascular of a therapeutic agent after absorption, which corresponds to the sum of its distribution and elimination; disposition includes both the alpha and beta portions of a declining serum dose concentration versus time curve. See Disposition, Elimination.