“…As pointed out in the introduction, not all spatial planning strategies described in the literature allow deriving predictions in the present scenario. Hence, we concentrate on the following planning strategies: First, the NN strategy, predicting that the closest target place is repeatedly chosen until all targets have been visited (Bureš et al, 1992;Gärling & Gärling, 1988;Gärling et al, 1986); and second, hierarchical planning strategies that can, in principle, be applied to the present scenario-the cluster strategy (Gallistel & Cramer, 1996;Wiener et al, 2004), the hNN method (Vickers, Bovet, et al, 2003), and the region-based planning strategy (Wiener & Mallot, 2003). All three hierarchical strategies have this in common: that the environment is structured into the different clusters or regions taken into account during planning.…”