neff: Calculates effective number of parties

In polrep: Calculate Political Representation Scores

Calculates effective number of parties

Description

This function calculates one version of the effective number of parties introduced by Laakso and Taagepera (1979). It can be used to estimate the effective number of groups in a population.

Usage

neff(x)

Arguments

x	Population vector

Details

This is one of two functions to calculate the number of effective parties. It gives 1 divided by the sum of Z squared. This function can be used to enumerate the effective number of parties, but also the effective number of groups in a population or representative body.

Value

Effective number of parties

Author(s)

Didier Ruedin

References

Laakso, M., and R. Taagepera (1979) The Effective Number of Parties: A Measure with Application to West Europe. Comparative Political Studies 12(1): 3-27.

See Also

neffProd, GTT, GTD2

polrep documentation built on Jan. 5, 2024, 3:01 a.m.