ABSTRACT
In using statistics it is necessary to make a clear distinction between populations and samples taken from the population. A population might for example. be represented by a collection of units such as books in a library or by the products resulting from a continuous chemical process. ln many cases the population is quite large. ln general, we desire estimates of parameters, such as the population mean and variance. These estimates are calculated from a sample taken from the population. Depending on the size of the population, the sample might represent anywhere from a fraction of I';,� to the entire population. To draw conclusions about the population from the sample taken, the method known as statistical inference must be used.
