Frank A Cowell and Christian Schluter

Published July 1998

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The performance of two broad classes of mobility indices is examined when allowance is made for the possibility of data contamination. Single-stage indices ? those that are applied directly to a sample from a multivariate income distribution ? usually prove to be non-robust in the face of contamination. Two-stage models of mobility ? where the distribution is first discretised and then a transition matrix or other tool is applied ? may be robust if the first stage is appropriately specified. We illustrate results using a simple but flexible simulation.