The following definition basically follows the one used by David Eppstein.

The official concepts and definitions, as used in the Current Population Survey, follow.

The simplest definitions follow after one identifies the clusters recursively.

The formal definition of an iterated function on a set X follows.

Following are definitions for columns in the tables on the next pages.

It did not matter that the definition followed the fact, rather than the other way around.

And then the most general definition of work can be formulated as follows:

Other definitions have followed, but all center on the fact that the plays cannot be easily assigned to the traditional categories of comedy or tragedy.

The following definitions follow the treatment in Baader et al.

The probability-theoretic definition of category utility given in and is as follows: