## Negative Binomial Distribution Calculator

Calculate probabilities and percentiles for a negative binomial distribution.

**Frequently Asked Questions (FAQs):**

**What is a negative binomial distribution, and why is it important?**- A negative binomial distribution models the number of trials needed to achieve a fixed number of successes in a sequence of independent Bernoulli trials. It's crucial in probability theory for scenarios involving rare events or trials with no predefined endpoint.

**What is the formula for calculating negative binomial distribution probabilities?**- The formula for calculating the probability of observing exactly
**r**successes in**x**trials, with a success probability of**p**, in a negative binomial distribution, is:

- Where
**x**is the number of trials,**r**is the number of successes,**p**is the success probability, and**{x-1 choose r-1}**is the binomial coefficient.

- The formula for calculating the probability of observing exactly
**How do I interpret negative binomial distribution probabilities?**- Negative binomial distribution probabilities provide the likelihood of achieving a specific number of successes in a sequence of trials. It's often used to model situations where you're interested in the number of trials needed to achieve a fixed goal.