The present research tested a quantitative model in which the sense of unfairness is determined by either the ratio of physical outcomes to inputs or the difference between psychological outcomes and inputs. Forty nine undergraduate students in Study 1 and eighty one students in Study 2 were asked to rate the fairness of the combinations of work hours and wages on nine point scales. The results suggest that the sense of unfairness of the work-wage combinations is related to the logarithmic function of the outcome/input ratio, and to linear function of the difference of estimated outcomes from estimated inputs. Implications were discussed in terms of the general quantitative models of fairness.
