# Conflict and Computation on Wikipedia:
## 4 Discussion  
The results described here provide novel evidence for the existence of an epoch-like structure of conflict and cooperation on Wikipedia, distinguished by behavioral motifs. When we model page editing as a finite state machine, we find that pages can be trapped in one or another subset of their computational subspaces, often for hundreds of days at a time. At the most coarse-grained level, this trapping places the system in either a low- or high-conflict state. In the high-conflict state, we also see an acceleration of activity by a factor of two or more. Subspaces are characterized by more than just overall levels of conflict: they have distinct motifs of interaction, including tit-for-tat (repeated reverting) in the low-conflict subspace, and propose-reject (C then R) and strong signals of vandal repair in the high-conflict subspace. The epoch structure revealed by our finite state analysis is defined by far more than just the density of reverts. As can be seen in the example time series in Figure 1, the low-conflict subspace can have long runs of reverting and edit warring. Low-conflict, in other words, does not mean zero conflict and may even mean norm violation; repeated reverting is likely to violate the \"three revert rule\" (3 RR) that prohibits a single user from making three reverts to a page in a row. In game theoretic accounts of behavior on Wikipedia, reverts can be likened to \"defect\" moves, and repeated reverts by different users are something we might expect from a tit-for-tat like strategy under noise [16]. The association of long strings of reverts with the low-conflict subspace fits with accounts that put tit-for-tat at the heart of successful resolution of collective action problems from associal beginnings [50]. The fact that they violate the Wikipedia-specific 3 RR norm suggests that this more ancient tit-for-tat strategy may still play an important functional role in managing conflict. Individuals may be banding together: past work on Wikipedia conflict has examined the influence of edit wars that draw in multiple mutually-reverting subgroups, and these more structured interactions may characterize the low-conflict subspace. In the case of edits to the [PERSON] page, for example, a network analysis finds three groups of antagonists: one group of administrators, and two groups associated with a particular point of view [10]. The patterns we describe here extend over thousands of edits; our epoch structure is on a longer timescale than the laws that describe short-term, repeated cooperation on timescales of minutes and hours [1]. It is consistent with findings of the importance of long-term system memory in the bursty structure of edit wars [13; 31; 51; 52; 53]. Our work goes beyond previous studies to explicitly construct an approximation to the full social grammar of system conflict [54]. Since the number of users far exceeds the number of states, each state is an irreducible coarse-graining of an (implicit) fine-grained, complete account of the mental states of hundreds of individuals acting in a context set by the text on the page itself. A natural language for the discussion of the transition between conflict and cooperation comes from the critical transitions literature. This work draws on tools from catastrophe theory, critical bifurcations, and phase transitions [55; 56]. They focus on the unusual and potentially chaotic dynamics that emerge from the interaction of large numbers of heterogeneously-coupled units. These accounts are often mechanism-neutral and focus on abstract properties of a time series of events. In the literature on critical transitions, for example, one looks for properties such as spatial correlation [57], critical slowing down [58] or flickering [59], and can apply their logic to clinical depression just as well as ecosystem collapse [60]. In its focus on discrete states, rather than continuous fields, our work is complementary to this tradition.