normal distribution

graph which shows the majority of a population to be concentrated around the average and fewer people located at the extremes, bell curve graph

The normal distribution, also called the Gaussian distribution, is an important family of continuous probability distributions, applicable in many fields. Each member of the family may be defined by two parameters, location and scale: the mean ("average", μ) and variance ("variability", σ2), respectively. The standard normal distribution is the normal distribution with a mean of zero and a variance of one (the green curves in the plots to the right). Carl Friedrich Gauss became associated with this set of distributions when he analyzed astronomical data using them , and defined the equation of its probability density function. It is often called the bell curve because the graph of its probability density resembles a bell.
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Noun
1. a theoretical distribution with finite mean and variance
(synonym) Gaussian distribution
(hypernym) distribution, statistical distribution
(classification) statistics

<statistics> (Or "Gaussian distribution") The frequency distribution of many natural phenomena such as the height or intelligence of people of a certain age and sex. The formula looks something like:
P(x) = e^(((x-m)/s)^2)
where P(x) is the probability of a measurement x, m is the mean value of x and s is the standard deviation.
Also known as a "bell curve" because of its shape.
(2003-10-25)

A probability distribution for a continuous random variable that is forms a symmetrical bell-shaped curve around the mean. This distribution has no skewness or excess kurtosis.