Cross-Impact Balance Analysis

Cross-Impact Balance (CIB) analysis is a semi-quantitative foresight method that turns a panel of qualitative expert judgments into a small set of internally consistent scenarios. Introduced by Wolfgang Weimer-Jehle in 2006, CIB describes a system as a set of descriptors, each of which can take one of several discrete future states, and asks experts to judge, pairwise, how strongly each state promotes or restricts every other state. These judgments form a cross-impact matrix; a balance algorithm then searches the combinatorial space of state combinations for configurations in which every descriptor's chosen state is the one most strongly supported by all the others. These self-consistent combinations are the scenarios. CIB has become a standard tool for building qualitative socio-technical scenarios, including the shared socio-economic pathways used in climate research.