migration.gini.total | R Documentation |

The Total Gini Index shows the overall concentration of migration with a simple number computed by comparing each cell of the migration matrix with every other cell except for the diagonal:

*G^T = \frac{∑_i ∑_{j \neq i} ∑_k ∑_{l \neq k} | M_{ij} - M_{kl} | }{ (2n(n-1)-1) ∑_i ∑_{j \neq i} M_{ij}}*

This implementation solves the above formula by a simple loop for performance issues to compare all values to the others at one go, although smaller migration matrices could also be addressed by a much faster `dist`

method. Please see the sources for more details.

migration.gini.total(m, corrected = TRUE)

`m` |
migration matrix |

`corrected` |
Bell et al. (2002) updated the formula of Plane and Mulligan (1997) to have |

A number between 0 and 1 where 0 means no spatial focusing and 1 shows that all migrants are found in one single flow.

David A. Plane and Gordon F. Mulligan (1997) Measuring Spatial Focusing in a Migration System.

*Demography***34**, 251–262M. Bell, M. Blake, P. Boyle, O. Duke-Williams, P. Rees, J. Stillwell and G. Hugo (2002) Cross-National Comparison of Internal Migration. Issues and Measures.

*Journal of the Royal Statistical Society. Series A (Statistics in Society)***165**, 435–464

`migration.gini.col`

`migration.gini.row`

`migration.gini.exchange`

`migration.gini.in`

`migration.gini.out`

data(migration.hyp) migration.gini.total(migration.hyp) # 0.2666667 migration.gini.total(migration.hyp2) # 0.225 migration.gini.total(migration.hyp, FALSE) # 0.2222222 migration.gini.total(migration.hyp2, FALSE) # 0.1875

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.