Instead, economic significance needs to be reconstructed. This is what the four models approach seeks to do by shifting to a dynamic approach to significance. In this approach, the economic analysis of the relation between an industry sector and the rest of the economy is instead constructed in terms of the dynamic interrelationship, which we may specify by examining the higher order moments of our master equation: specifically, how a change in CI activity (∆CI) affects aggregate economic activity (∆Y)