Tests of expectancy theory predictions of effort: A simulation study comparing simple and complex models

The authors summarize existing studies of expectancy theories of work effort and conclude that simple additive models generally predict effort as well as, or better than, more complex multiplicative ones. An attempt is made to explain the empirical findings using a computer simulation. The results of the simulation indicate that reasonable amounts of measurement error invalidate attempts to show that one combination of valence, expectancy, and instrumentality is a better predictor of work effort than any other. The authors conclude that even though questions regarding complex interactions cannot be answered, valence, expectancy, and instrumentality, taken independently, appear to be important determinants of work effort and point out areas where future research is needed.