The Grubel–Lloyd index measures intra-industry trade of a particular product. It was introduced by Herb Grubel and Peter Lloyd in 1971.

where Xi denotes the export, Mi the import of good i.

If GLi = 1, there is a good level of intra-industry trade. This means for example the Country in consideration Exports the same quantity of good i as much as it Imports. Conversely, if GLi = 0, there is no intra-industry trade at all. This would mean that the Country in consideration only either Exports or only Imports good i.

References

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  • Grubel, Herbert G.; Lloyd, Peter J. (1971). "The Empirical Measurement of Intra-Industry Trade". Economic Record. 47 (4): 494–517. doi:10.1111/j.1475-4932.1971.tb00772.x.
  • Grubel, Herbert G.; Lloyd, Peter J. (1975). Intra-industry trade: the theory and measurement of international trade in differentiated products. New York: Wiley. ISBN 0-470-33000-7.