Downton’s bivariate exponential distribution has been a popular model for hydrological sciences. However, it seems that no explicit expressions for its product moments are available. In this short note, we provide a direct derivation of a general expression for the product moments and also...

In this paper, we derive an exact test for a column of the covariance matrix. The test statistic is calculated by using a single observation. The exact distributions of the test statistic are derived under both the null and alternative hypotheses. We also obtain an analytical expression of the...

Empirical studies on food expenditure are largely based on cross-section data and for a few studies based on longitudinal (or panel) data the focus has been on the conditional mean. While the former, by construction, cannot model the dependencies between observations across time, the latter...