The Mathematics of Expectation States Theory

Since 1977, performance expectations, the central concept of expectation states theory (EST), has been calculated using a graph model. I restate that model as a single equation, which takes as inputs only (1) relevance of status characteristics and (2) counts of the number of characteristics at different levels of relevance. The equation model is useful for deriving deductions from EST; I demonstrate this by showing that status characteristics do not always exert declining marginal effects, and by reexamining Fisek's familiarity theorem. The equation model also should be useful for incorporating performance expectations into other mathematical models; I demonstrate this by showing how it may be incorporated into Skvoretz and Fararo's dynamic model of hierarchy formation. Finally, I show that extensions to the basic graph model of EST, such as allowing sources of performance evaluations, can be incorporated easily into the equation model.