Mysterious multiculturalism: The risks of using model-based indices for making meaningful comparisons

In this article, we discuss key problems of model-based indices and their indicators used by the students of cross-national differences in the field of immigration, integration and citizenship policies. Model-based indices aggregate scores on a variety of indicators. We scrutinize the risks of aggregation by looking closely at the measurement of multiculturalism in the Netherlands. We do so through a critical analysis of the measurement of multicultural policies provided by the Multicultural Policy Index and the corresponding indicators used in the Indicators for Citizenship Rights for Immigrants for the Netherlands since the 1980s. Our findings demonstrate that problems lie not in faulty scoring of individual indicators, but with the aggregation of those scores as measurements of a larger model. Most indicators more or less adequately score for policy developments in the Netherlands, but can hardly be considered to indicate multiculturalism. As we show, a wide variety of indicators, scoring policies in differing domains, cannot be assumed to measure the same coherent, but abstract, entity: 'Multicultural Policies', let alone a 'Multicultural Model'.