In economics and marketing a universe is a population to be studied or measured.
In economics a population to be measured is described as a "universe", and the measures which are generated are intended to reflect the behavior of that population.
The word has a similar meaning in marketing, where it describes the activity in a given population.
For example, ASCAP measures airplay in different radio "universes" to determine royalties for different songs, because e.g. air play in the "classical" universe is compensated differently from popular music.
For example, a hair dye ad campaign may buy 1000 Gross Rating Points (GRP) in the Women 25-44 universe in order to target that particular audience, rather than a demographic irrelevant to their product.