When you estimate a number you decide approximately, or roughly, how big that number is. To estimate accurately, you need to have a good understanding of the value and order of numbers. A number line ...

IN ecological work it is often necessary to have comparative estimates of the numbers of organisms in a large number of samples. An exact valuation may not be required, but an approximate numerical ...

Only a few countries have official population statistics which are sufficiently accurate to produce reliable estimates of death rates at high ages. For other countries, there are several methods which ...

This paper presents the results of a study with two main objectives: (1) to investigate an extension of some principles recently developed in the theory of cluster sampling, and (2) to determine the ...