Measuring language diversity in urban ecosystems

Talking about linguistic diversity is one thing, knowing about it is an­other. Linguistic diversity has become a prominent, but vague catch­phrase in public opinion circumscribing a range of societal phenomena from multi-lingual education to multi-ethnicity. A specification of what the concept really addresses can help to establish a more appropriate convention of the term. The objective of this paper is to put the term on scientific grounds and see how linguistic diversity can be captured quantitatively. For this undertaking, we look at other disciplines prof­iting from their rich experience of some sixty years of scientific inquiry in the field of diversity measurements, we see how their conception of diversity ties into the linguistic framework, and we make reasonable extensions to the basket of diversity indices. Thus we link ecology, biology, information science, and linguistics in the endeavor of finding apt measures for understanding diversity. Having derived and adjusted these measures, they are applied to a specific case, that is, the mea­surement of multilingualism in St. Georg, Hamburg.