migration.indices (version 0.3.1)

migration.gini.row: Rows Gini Index

Description

The Rows Gini index concentrates on the "relative extent to which the destination selections of out-migrations are spatially focused": $$G^T_R = \frac{\sum_i \sum_{j \neq i} \sum_{h \neq i,j} | M_{ij} - M_{ih} | }{ (2n(n-1)-1) \sum_i \sum_{j \neq i} M_{ij}}$$ This implementation solves the above formula by computing the dist matrix for each row.

Usage

migration.gini.row(m)

Arguments

m

migration matrix

Value

A number between 0 and 1 where 0 means no spatial focusing and 1 shows maximum 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.col migration.gini.row.standardized

Examples

# NOT RUN {
data(migration.hyp)
migration.gini.row(migration.hyp)  # 0
migration.gini.row(migration.hyp2) # 0.02083333
# }