Distribution Fitting Software & Articles

Negative Binomial Distribution

EasyFit: select the best fitting distribution and use it to make better decisions. learn more
EasyFit Screenshot - Click To Enlarge
Download Free Trial


- number of successes (positive integer)
- continuous probability of a single success ()



Probability Density Function (PDF)

Negative Binomial distribution PDF

Negative Binomial Distribution Fitting

EasyFit allows to automatically or manually fit the Negative Binomial distribution and 55 additional distributions to your data, compare the results, and select the best fitting model using the goodness of fit tests and interactive graphs. Watch the short video about EasyFit and get your free trial.

The video content presented here requires a more recent version of the Adobe Flash Player. If you are you using a browser with JavaScript disabled please enable it now. Otherwise, please update your version of the free Flash Player by downloading here.

Negative Binomial Distribution Graphs and Properties

EasyFit displays all graphs and properties of the Negative Binomial distribution, presenting the results in an easy to read & understand manner. EasyFit calculates statistical moments (mean, variance etc.), tail probabilities depending on the distribution parameters you specify.

Random Numbers from the Negative Binomial Distribution

You can easily generate random numbers from the Negative Binomial distribution in a variety of ways:

  • directly from EasyFit
  • in Excel sheets using the worksheet functions provided by EasyFitXL
  • in your VBA applications using the EasyFitXL library

Excel Worksheet and VBA Functions

EasyFitXL enables you to use the following functions in your Excel sheets and VBA applications:

Function Name
NegBinomialPdf Probability Density Function
NegBinomialCdf Cumulative Distribution Function
NegBinomialRand Random Numbers
NegBinomialMean Mean
NegBinomialVar Variance
NegBinomialStdev Standard Deviation

Learn more: EasyFit Help on the Negative Binomial distribution