302 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 
whence 
(250-5) 
k 
ae, ¢ 
Supplementary hypothesis (d) thus corresponds to an expo- 
nential decrease in the elasticities 3(0). 
Characteristics of the Exponential Model 
251. We have here from (220-1), (220-6) and (220-14) 
¢ (u J 
(251-1) 
_ 
+0 u 
J 
A 
Using this expression, the formulae applying to the exponen- 
al model are derived directly from those already given (1). 
They are presented in the table below (2). 
1) Relations (223-7), (231-5), (227-3), (232-3), (224-2), (225-3), (226-1), 
226-9), (226-2), (226-3), (228-12), (229-5), (233-2), (233-3), (25I-5) and 
(251-6). 
2) The notation Ry represents the maximum values of RB for i—o 
‘117 Allais - pag. 106