This ecological study describes the cholera epidemic in Harare during 2008-2009 and identifies patterns that may explain transmission. Rates ratios of cholera cases by suburb were calculated by a univariate regression Poisson model and then, through an Empirical Bayes modelling, smoothed rate...

Two interesting results encountered in the literature concerning the Poisson and the negative binomial distributions are due to MORAN (1952) and PATIL & SESHADRI (1964), respectively. MORAN's result provided a fundamental property of the Poisson distribution. Roughly speaking, he has shown that...

In many practical situations bivariate probability distributions are used whose marginals are of the same form. Sometimes however, in cases of a not too good fit, one of the marginals appears to describe the corresponding observed data exceptionally well while the other provides a rather poor...

This paper discusses the probability of exploiting price variations that may occur during the survey period of any household expenditure survey in order to identify heterogeneous demand responses to discrete price changes. This is possible since expenditure survey contain usually a large number...

Economic history reveals that different countries over different time periods suffered from severe shortage of currencies of small denominations. Due to the frequency and severity of these incidents, first Cipolla (1956) and later Sargent and Velde (2002) named this phenomenon as ``the big...

The paper presents theoretical framework of demand and supply of currencies of small denominations. In our framework both demand and supply equations emerge out of an optimization framework. Demand functions for small denominations are obtained from a linear expenditure system. Our main...

Distributions are often characterised by their ageing properties, failure rates, residual life, etc. New failure distributions based on ageing properties are derived and some simple graphical techniques based on the ageing properties of distributions are demonstrated.