Beta Function - Incomplete Beta Function

The incomplete beta function, a generalization of the beta function, is defined as

For x = 1, the incomplete beta function coincides with the complete beta function. The relationship between the two functions is like that between the gamma function and its generalization the incomplete gamma function.

The regularized incomplete beta function (or regularized beta function for short) is defined in terms of the incomplete beta function and the complete beta function:

Working out the integral (one can use integration by parts) for integer values of a and b, one finds:

The regularized incomplete beta function is the cumulative distribution function of the Beta distribution, and is related to the cumulative distribution function of a random variable X from a binomial distribution, where the "probability of success" is p and the sample size is n:

Read more about this topic:  Beta Function

Famous quotes containing the words incomplete and/or function:

    Someone once asked me why women don’t gamble as much as men do, and I gave the common-sensical reply that we don’t have as much money. That was a true but incomplete answer. In fact, women’s total instinct for gambling is satisfied by marriage.
    Gloria Steinem (b. 1934)

    If the children and youth of a nation are afforded opportunity to develop their capacities to the fullest, if they are given the knowledge to understand the world and the wisdom to change it, then the prospects for the future are bright. In contrast, a society which neglects its children, however well it may function in other respects, risks eventual disorganization and demise.
    Urie Bronfenbrenner (b. 1917)