Random number
From Free net encyclopedia
In statistics, a random number is a single observation (outcome) of a specified random variable. Where no distribution is specified, the continuous uniform distribution on the interval [0,1) is usually, but not always, intended.
In an informal sense, there is some circularity in this definition as the idea of random variable itself rests on the concept of randomness. A number itself cannot be random except in the sense of how it was generated.
Informally, selecting a number at random with uniform distribution on some set requires that all elements of that set were equally probable as outcomes before the selection. In particular, this means that knowledge of earlier numbers generated by this process, or some other process, do not yield any extra information about the next number. This is equivalent to statistical independence.
See also
de:Zufallszahl es:Número aleatorio he:מספרים אקראיים ja:乱数列 pt:Número aleatório ru:Случайная величина fi:Satunnaisluku zh:随机数