“…From a different perspective, our decision to focus the presentation first on the setting of zigzag modules is motivated by extensive theoretical and algorithmic study on zigzag persistence [10,11,17,14,15,23,26,34,36], and the large number of concrete applications in mobile sensor networks, image processing, analysis of time-varying metric spaces/graphs that give rise to zigzag persistence [1,21,27,28,32]. In particular, in [27,28], zigzag persistence of graphs, partitions, or homology groups are induced as signatures of time-varying metric data. This motivates us to find stable invariants for zigzag persistence valued in other than the category of vector spaces.…”