The comparison of usage and availability measurements for evaluating resource preference (PREFER)

The program PREFER performs calculations described in Johnson (1980) to
determine the preference of J individuals for I components (for example,
habitat types or kinds of foods) using availability and use data. The method is
based on ranks of the components by availability and by use. Accordingly, a
virtue of the method is that it provides comparable results whether a
questionable component is included or excluded from consideration. Other
methods of determining resource preference depend critically on the array of
components that the researcher deems available to the animal; such decisions
are often arbitrary. PREFER tests the hypothesis that all components are
equally preferred and compares components using a multiple comparison
procedure.

The purpose of PREFER is to determine the preference of individuals for certain
habitat types or kinds of foods.