Simulating and reconstructing language change

In this work we probe phylogenetic algorithms for their ability to reconstruct historic language relationships. We present a formal model for the development of languages incorporating vertical (genealogical) and horizontal (language contact) effects. As a distinctive feature, we also added a geographic model to mimic the effects of constrained population movements. Using our model, we generated a large number of simulated language histories whose results were analyzed by a variety of established phylogenetic algorithms. Therein, we systematically investigated the effects of different contact intensities and of geographic as well as genealogic topologies. We found that tree-based algorithms are robust under a variety of different settings and are capable of inferring (parts of) the relationships correctly even under high levels of network-like influences. We also studied the SplitsTree algorithm which should be more appropriate to cope with network-like effects. However, although SplitsTree clearly performs better in some settings, it generally shows a rather erratic behavior