5.6 Summary

Table 5.1 summarises some important distributions.

TABLE 5.1: Summary of common distributions
Reference Type Mean Variance Notes
Poisson Sect. 5.1 Discrete: x=0,1,2, μ μ μ>0
Binomial Sect. 5.2 Discrete: x=0,1,,n np np(1p) 0<p<1 and n1 an integer
Geometric Sect. 5.3 Discrete: x=0,1,2, 1p 1pp2 0<p<1
Exponential Sect. 5.4 Continuous: x>0 μ μ2 μ>0
Normal Sect. 5.5 Continuous: <x< μ σ2 <μ<; σ>0