This paper examines the implicit links between models containing ordinal variables and their underlying unquantified counterparts that are necessary to make the former viable theoretical constructions. It is argued that when the underlying unquantified structure is unknown, the permissible...

Three definitions of hysteresis in dynamic economic models are considered in order of their increasing ability to project history onto the present in a significant way. The third of these definitions is based on the substitution of 'historical' for 'logical' time in the model's dynamic structure.