normal distribution(redirected from Normality (statistics))
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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.
probability distribution a mathematical function that assigns to each measurable event in a sample group the probability that the event will occur.
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:
(in statistics) a theoretic distribution frequency of variable data usually represented graphically by a bell-shaped curve that reaches a peak about the mean.
normal distributionA 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.
Synonym(s): bell-shaped curve, normal distribution.
normal distributionGaussian 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.
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.
see age distribution.
the distribution has two regions of high frequency of observations separated by a zone of low frequency.
a probability distribution associated with two mutually exclusive outcomes.
a nonrandom distribution with observations aggregating about geographic or temporal variables. May be deceptive and merely reflect the distribution of an uneven population.
a table or graph of the frequency of occurrence of each value of a variable.
see normal distribution (below).
may apply to sampling without replacement of a finite population.
a distribution which is normal when the log values of the variable are considered.
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.
the distribution (population) that was originally sampled.
see poisson distribution.
distributed at regular intervals of time or space; all values within its given interval are equally likely.
an increase in frequency in one sex, which includes neutered males and neutered females. Called also sex-linked or sex-associated.
a distribution in which the curve illustrating it is not symmetrical but has a long tail on one or other side of the graph.
variations in distribution related to position in space, e.g. close to the door of a barn.
variation in distribution related to time, e.g. occurrence of disease incidents after visits by veterinarians, inseminators, feed salesmen.
1. agreeing with the regular and established type. When said of a solution, it denotes one containing one chemical equivalent of solute per liter of solution; e.g. a 0.5 normal (0.5 N) solution has a concentration of 0.5 Eq/l. The use of standard units (Eq/l) is now generally preferred in pharmacy and clinical medicine although elsewhere molarity (M) is used.
2. in the context of infectious diseases, not immunized or infected.
3. statistically speaking, the values of a variable which follow a bell-shaped or Gaussian distribution.
see normal distribution.
limits of the classification of 'normal' in the results of a test.
contains 0.9% sodium chloride. Called also isotonic saline.