Estimation of Parameters of the POISSON with Excess Zeroes and Negative Binomial with Excess Zeroes Distributions

✍ Scribed by Lachenbruch, Peter A.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1975
• Weight: 199 KB
• Volume: 17
• Category: Article
• ISSN: 0006-3452
• DOI: 10.1002/bimj.19750170602

✦ Synopsis

In many observed processes, data is fit well by a common distribution except for an excess of numbers of the zero class. This may be due to a threshold phenomenon in which no response occurs until a concomitant variable reaches a certain level, and the response is governed by the common probability law. Two such common distributions are the POISSON and negative binomial. Much of the theory of estimation for the POISSON with zeroes and negative binomial with zeroes may be found in JOHNSON and KOTZ (1969). In this paper some graphical aids will be presented for fitting these distributions.