Kazagli and Bierlaire (2014) propose to replace paths by abstract geo-marked items denoted by Mental Representation Items (MRIs). An MRI is not necessarily a specific location or landmark. An area like a city center can act as an MRI. MRIs are used in the choice set generation phase and not only in the choice set model as an explanatory variable. However, practical problems can arise when MRIs need to be derived from recorded data.