Models of ecological inference (EI) have to rely on crucial assumptions about the individual-level data-generating process, which cannot be tested because of the unavailability of these data. However, these assumptions may be violated by the unknown data and this may lead to serious bias of...

In a recent paper Becker et al. have analysed the pattern of voting at the UK's 2016 Referendum on membership of the EU, testing four hypotheses with a wide range of variables. Re-analysis of their data identifies a number of problems of confounding resulting from collinearity among the...