A manufacturer of jet engine turbines has an order to produce 50 turbines. Since about 20% of the turbines do not make it past the high-velocity spin test, the manufacturer will actually have to produce more than 50 turbines.
The negative binomial distribution has two parameters: Probability and Shape. The Shape parameter specifies the r th successful occurrence. In this example you would enter 0.8 for the Probability parameter (80% success rate of the spin test) and 50 for the Shape parameter (Figure 88, Negative Binomial Distribution).
