Where Was Alexander the Great in 325 BC? Toward Understanding History Text with a World Model

We present a toy world model for interpreting textual descriptions of the movement record of a historical figure such as Genghis Khan or Napoleon. We cast the problem of document understanding as the task of finding episodes that do not violate the soft constraint conditions derived from the document. The model thus allows us to infer his or her locations by finding multiple solutions of an optimization problem. Our experimental results using Wikipedia text on Alexander the Great demonstrate that such inference can indeed be performed with reasonable accuracy. We also show that the information obtained from such inference is useful in solving a hard coreference resolution problem.