ABSTRACT
Variate independence is defined by a relationship that will be described in this section between the different curves; / ( x ) , / ( y ) and f (x ,y ) . In con trast to the mathematical definition of independence, the term randomness is difficult to define without also including a detailed description of how samples are selected. Unfortunately, more labor is often required to de scribe the practical details of a process which is a means to an end than is required to describe the end or goal itself. According to Kendall and Buckland’s A Dictionary of Statistical Terms:
random selection is a method of selecting sample units (subjects) such that each possible sample has a fixed and determinate prob ability of selection. Ordinary haphazard or seemingly purposeless choice is generally insufficient to guarantee randomness when carried out by human beings and devises such as tables of random sampling numbers, or analog machines, are used to remove subjective biases inherent in personal choice.
