Enduring Rivalry Analysis

Persistence and recurrence. An enduring rivalry is a pair of states locked into repeated militarized confrontations over an extended period, whereas isolated disputes are single or sporadic. Diehl and Goertz operationalize the distinction with thresholds on the number and temporal spacing of disputes, separating enduring rivalries from proto-rivalries and isolated conflicts. The point is that enduring rivalries are coherent relationships with their own histories.

Borrowed from evolutionary biology, it holds that rivalries lock in quickly at a basic level of hostility, then persist with little change for long stretches, shifting abruptly only when major political shocks (such as world wars, regime changes, or decisive settlements) disturb the equilibrium. This contrasts with views of rivalry as gradually evolving, and it implies that rivalry termination usually follows shocks rather than slow drift.

Dyadic conflict analysis typically uses the dyad-year and models the probability of a dispute in each year. Rivalry analysis aggregates recurring disputes between the same pair into a single relationship and explains the rivalry's onset, dynamics, and end. They share data (MIDs, dyads) but differ in unit and temporal framing: rivalry analysis adds the recognition that disputes within a rivalry are connected episodes of one ongoing antagonism.