La teoria microeconomica e la legge di Fisher-Clarkdi Goodman-Kruskal


  • Alighiero Erba Università di Roma “La Sapienza”



In this paper the author wishes to discuss some of the hypotheses which seek to explain the "law of the development stages" (or Clark-law). In a situation where the productive sector appears to be more and more influenced by tertiarization phenomena (at least in the developed countries), the author examines the causes of what happened. The author concludes that the explanations of the development of the tertiary sector are mainly based on the needs (true or supposed) to which this sector answers. There is, instead, little or no discussion on the constraints that the goods (products of the primary and secondary sector) and the services (products of the tertiary sector) impose to their purchaser. These could be the real cause of the changes in the demand of households and firms. The author remarks that, due to their tangibility, the goods impose a particular constraint to their purchaser (both in the case when the purchase is made for consumption or capital expansion). This constraint is not adequately stressed at the microeconomic level and is represented by the need for an adequate space. In fact the purchaser of a good must allocate it in a space which is under his control; otherwise he can loose the property of it. This physical space could be his own fridge (or, in the limit, his own stomach) if the good is food. It could also be the living room if the good is a TV set. It could finally be a building if the good is a machinery. The purchase of services, in contrast, does not impose any space constraint, but a constraint upon time. The user, to be such, needs an adequate time to benefit from it. In this way the author poses the foundations for a revised consumption theory. In fact, according to the previous considerations, the consumer would split his endowment into goods purchases and service purchases, (by assuming no saving) considering his own time and space constraints. In the long run it has been noticed a remarkable increase of leisure time by the consumers, (as a consequence of the dramatic reduction of the working time) whereas to some phenomenon has not been observed for the disposable space. The author concludes that the "constraint-system" has produced (through the mechanism described above) a shift of the demand from goods to services and, as a consequence, a real phenomenon of tertiarization of the economy from the supply-side. On the other hand the phenomenon of tertiarization originates not only from changes within the household sector, but also from processes generated within the firm sector. In fact the effect of a time-saving technological development (keeping the product constant) can induce the enterpreneur to increase the production by purchasing more machinery. In this case it is not unlikely to observe the need for additional space to allocate the new durables. Together with (or alternatively to) the acquisition of more durables, the enterpreneur could be induced (to face competition, for reasons connected with the organization, for lack of space and so on) to use the resources which are free in order to increase e.g the quality or the distribution of the product by using e.g engineering services or marketing services or other. In this way the possibility of an acceleration of the development of the tertiary connected to production is generated. This could take place either implicitly, that is contained within the primary and secondary sector, or explicitly. This phenomenon could be considered as another cause of the development of the tertiary sector.

How to Cite

Erba, A. (1990). La teoria microeconomica e la legge di Fisher-Clarkdi Goodman-Kruskal. Statistica, 50(1), 39–58.