ABSTRACT
In many real situations, it is not really necessary to represent each member of S+, the set of all source words, by a code word, a member of A+. For instance, if the source text is a chunk of ordinary English prose, we can be reasonably certain that we will not have to transmit nonsense words like “zrdfle” or “cccm.” However, it does not seem that there is any great advantage to be had by omitting part of S+ from consideration, and there is some disadvantage-the discussion gets complicated, quarrels break out, anxieties flourish.
