“…where the number of statistics is equal to the number of parameters to be estimated -they are restricted to problems that can be described in terms of models that belong to the exponential family (Lehmann & Casella, 1993;Didelot et al, 2010). As previous authors have pointed out it is necessary to develop methods that construct sets of statistics that are (at least approximately (Le Cam, 1964;Kusama, 1976)) sufficient (Joyce & Marjoram, 2008;Nunes & Balding, 2010;Fearnhead & Prangle, 2010a,b). It is either this, or reinterpreting ABC-based inferences not as approximations to the full Bayesian (and thus likelihood-based) apparatus but as inference procedures in their own right (Wilkinson, 2008;Drovandi et al, 2011), potentially systematically biased or for approximate models.…”