This **negative binomial calculator** can help you calculate the negative probability based on the number of trials (n), number of successes (x) and probability of success on a single trial (p).

## What is a negative binomial experiment?

In statistics, a negative binomial experiment is an experiment having the following *particularities*:

■ The experiment is made of *x repeated trials*, while each trial can be considered either *a success or a failure*.

■ On every trial, the *probability of success is constant*, while the *trials are independent* as the outcome on a trial does not have any impact on the other trials success or failure.

■ Finally, a negative binomial experiment ends only when a *specific number of successes established in advance is achieved*.

## How does this negative binomial calculator work?

The algorithm behind this *negative binomial calculator* uses the following formula:

**NB(n; x, P) = _{n-1}C_{x-1} * P^{x} * (1 - P)^{n – x}**

Where:

p = Probability of success on a single trial

n = Number of trials

x = Number of successes

28 Jul, 2015