The estimation of the sample size is a crucial part of the planning process of a survey and it can be accomplished in different ways, some of them require information not available or that may be obtained with a substantial cost. The estimation of the sample size can be done by using the design...

Groundwater exploitation for rural water supply without proper understanding of its chemistry and changes that may be induced by physical processes and anthropogenic activities may be counter productive. This study examines the effect of season on the physico-chemical concentrations in...

The estimation of the sample size is a crucial part of the planning process of a survey and it can be accomplished in different ways, some of them require information not available or that may be obtained with a substantial cost. The estimation of the sample size can be done by using the design...

Choosing the number of stocks to hold in a portfolio can significantly affect its risk. We use daily observations for traded equity returns in the US, UK, Japan, Canada and Australia from 1975 to 2011 to simulate portfolios and calculate several measures of risk, including heavy tailed. For each...