Wefocuson the zero-catchproblemofCPUE (catchperunit effort) standardization. Because the traditional CPUE model with a log-normal error structure cannot be applied in this case, three methods have often been utilized as follows: (1) Ad hoc method adds a small constant value to all response variables. (2) Catch model with a Poisson or negative-binomial (NB) error structure. (3) Delta-type two-st...

In statistical process control, the primary method used to monitor the number of nonconformities is the c-chart. The conventional c-chart is based on the assumption that the occurrence of nonconformities in samples is well modeled by a Poisson distribution. When the Poisson assumption is not met, the X-chart (individuals chart) is often used as an alternative charting scheme in practice. In thi...

Count data often exhibit overdispersion and/or require an adjustment for zero outcomes with respect to a Poisson model. Zero-modified Poisson (ZMP) and zeromodified generalized Poisson (ZMGP) regression models are useful classes of models for such data. In the literature so far only score tests are used for testing the necessity of this adjustment. For this testing problem we show how poor the ...

The standardised mortality ratio is the ratio of deaths observed, D, to those expected, E, on the basis of the mortality rates of some reference population. On the usual assumptions--that D was generated by a Poisson process and that E is based on such large numbers that it can be taken as without error--the long established, but apparently little known, link between the Poisson and chi 2 distr...

A nano-displacement sensing method for micro-opto-electro-mechanical-systems (MOEMS) is proposed. The method is based on a square attice photonic crystal (PC) made of dielectric silicon posts, mounted on a micro mechanical flexure. The flexure is fixed at one end and is free to ove at the other, to enable elastic deformations that, by being transferred to the photonic crystal array, modify its ...

Simple models of molecular evolution assume that sequences evolve by a Poisson process in which nucleotide or amino acid substitutions occur as rare independent events. In these models, the expected ratio of the variance to the mean of substitution counts equals 1, and substitution processes with a ratio greater than 1 are called overdispersed. Comparing the genomes of 10 closely related specie...