Following previous work (Riedl and Biemann 2012; Glavaš, Nanni, and Ponzetto 2016; <cite>Koshorek et al. 2018)</cite> , we also adopt the standard text segmentation measure P k (Beeferman, Berger, and Lafferty 1999) as our evaluation metric. P k score is the probability that a model makes a wrong prediction as to whether the first and last sentence of a randomly sampled snippet of k sentences belong to the same segment (i.e., the probability of the model predicting the same segment for the sentences from different segment or different segments for the sentences from the same segment).