Quantification of the similarity of niches and, in particular, of the similarity in the use of resource type. The resources involved can be food, but also, for instance, may be aspects of the habitat.

The “no difference” or “no association” hypothesis, to be tested, usually by means of a significance test, against an alternative hypothesis.

Examples:

The species composition (or species body size or species phenology) is the same in different habitat types.

The species composition is the same in natural areas and areas disturbed by anthropogenic activities.

The species composition is the same in different geographical areas.

The species composition is the same in different seasons;

Grassland species composition is the same in farmed and not-farmed fields (or in inland and coastal dune habitats or….).

Grassland plants have same type of leaves in cultured and not cultured fields (or inland and coastal dune habitats or….).

The diversity of cat mantles is the same comparing blocks of buildings in the same town or different towns

Colour of flowers is the same in grasslands, dunes, woodlands, coastal chaparral….