SEMAINE D ETUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 
XA 
Here are the main results 
“ABL 
\ vera gr” 
Average 
rXNC 
The estimates of ©, are of the same order of magnitude for 
he United States from 1880 to 1956, and for the United States, 
France and Great Britain : Get 
2. 
JUSTIFICATION OF THE EXPONENTIAL MODEL WITH RESPECT 
TO ITS HYPOTHESIS 
Hypothesis (d): The Relative Productivity of Primary Inputs 
322. Hypothesis (d) (3) cannot be confirmed directly from 
experience, and can only be justified by the concordance of 
the conclusions flowing from it with observed data. 
However, a priori, it seems intuitively reasonable to as- 
sume at least as a first approximation that production elasticities 
decrease exponentially with time. 
Further, this assumption is closely related to hypothesis (b, 
of invariance of the function 3(8) over time. In fact, postulat- 
ing the invariance of the capitalistic production function of 
the productive system over time implies not merely the cons- 
‘ancv of the function 3(8), but, also, if we think it over, the fact 
elow 
Allais - pag. 125