SEMAINE D'ÉTUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 
505 
lative prices are determined by technology. Demand (i.e. consu- 
mers’ preferences) then determine the relative quantities to be pro- 
duced. Prices, therefore, emerge as a sort of indexes of relative 
efforts that society is obliged to put into each single unit of the 
various commodities. The two interpretations of prices are indeed 
-adically different. 
The central part of Professor DoRFMAN’s comment may now be 
looked at from this point of view. I am, of course, aware that neo- 
classical economists did deal with problems of production. But I 
am raising objections to them when they try Zo extend to produced 
commodities the interpretation of prices and quantities which has 
>merged from a model for scarce goods. Of course, I am not raising 
any objection — on the contrary I am approving — when they 
come near to the interpretation of prices and quantities for produced 
commodities which I have hinted at above, as for example MARSHALL 
himself does in his analysis of the long run, and as indeed LEONTIEF 
does as well 
KOOPMANS 
[ agree with Dr. PASINETTI that the phenomenon of learning ... 
production has been insufficiently recognized in economic the-i: 
[he same applies to learning in consumers’ choice. As regards 
production, I wish to draw attention to a paper by W. Z. HrrscxH, 
Firm Progress Ratios, « Econometrica », April 1956, in which some 
attempts to quantifv the learning process in production are re- 
ported on. 
PASINETT 
[ thank Professor Koopmans for his kind bibliographical sus 
zestion. I consider in fact Mr. HirscH’s paper, referring to thc aii- 
frame industty, as one of the many empirical studies which confirm 
he necessity of the type of analysis which I am trying to propose. 
101 Pasinett: - pag. 123