migration.gini.exchange.standardized {migration.indices}

Standardized Exchange Gini Index

Description

The standardized version of the Exchange Gini Index (migration.gini.exchange) by dividing that with the Total Flows Gini Index (migration.gini.total):

G^{T*}_{RC, CR} = 100\frac{G^T_{RC, CR}}{G^T}

As this index is standardized, it "facilitate comparisons from one period to the next" of the exchange indices.

Usage

migration.gini.exchange.standardized(
  m,
  gini.total = migration.gini.total(m, FALSE)
)

Arguments

m

migration matrix

gini.total

optionally pass the pre-computed Total Flows Gini Index to save resources

Value

A percentage range from 0% to 100% where 0% means that the migration flows are uniform, while a higher value indicates spatial focusing.

References

• David A. Plane and Gordon F. Mulligan (1997) Measuring Spatial Focusing in a Migration System. Demography 34, 251–262

See Also

migration.gini migration.gini.exchange

Examples

data(migration.hyp)
migration.gini.exchange.standardized(migration.hyp)  # 25
migration.gini.exchange.standardized(migration.hyp2) # 22.22222