In sociology, the term is applied in the active sense to a person or group of people who tend to create, influence, or set trends. In politics, the term more often applies in a metaphorical sense to describe a geographic region where political tendencies match in microcosm those of a wider area, such that the result of an election in the former region might predict the eventual result in the latter. In a Westminster-style election, for example, a constituency, the control of which tends frequently to change, can mirror in its popular vote the result on a national scale.