296 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 
For k there are many reasons for believing that its value does 
not differ very much from unity. 
À precise estimate of À appears to be particularly difficult to 
make, but as I have already said, the analysis in the appendix 
shows that under very general conditions, we can consider that 
A col 
7) The general model and its exponential variant appear to be 
justified by the facts both as to their hypotheses and their conse- 
juences. : 
The third part of my paper shows that the course of event to 
what one would expect if the general model were be correct, and as 
far as can be judged, reality does not differ very much from the 
exponential variant of the general model. 
I must particularly stress the striking agreement between the 
conclusions of the theory and the practical constancy of the estimates 
of the capital output ratios y and of the estimates of the coefficient 
© ($ 321, 323 and 324) (Table VII). 
8) Finally four different applications are given in the fourth 
part of my paper (Table VIII). These are the following: 
First, it is possible to estimate what could be obtained from an 
ncrease in the capital output ratio y,=C/R,. It is shown that 
developed countries are in the neighbourhood of an optimum capi- 
‘alistic structure ($ 410-411). 
Secondly, the diminution of the real national income as a con- 
sequence of population increase is estimated to be of the order of 
magnitude of kO p. For the United States, this figure is of the order 
of magnitude of 79% (§ 420-421). 
Thirdly, the model is used to study the problem of estimating 
the influence of the capitalistic structure on differences in produc- 
lvity between France and the United States. As far as can be 
judged, existing differences must be explained bv other factors 
(§ 430-433). 
11] Allais - pag. 300