SEMAINE D'ÉTUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 
with 
(223-7) 
v 
where 1 and ç are functions of time (§ 210). 
It follows that the expression for amortization oc) facror 
income 1s invariant over time and depends only on in = 
erence i- p. 
The process considered is therefore, following the definition 
given above, a quasi stationary process with a variable growth 
rate, and the relationships derived under this hypothesis are 
applicable () (2) (3) 
) $ 120. 
() Where the function ? depends oa time, we hav 
JX) 
Tquation (222-3) can then br 
we <‘ 
2) 
vhence 
3) 
ct, €) 
and the integral equation (2. 
IN K ti 
0 
must hold for all valur 
If we write 
i, 0) 
rs 
E- 
nen 
> 
ak 
6) 
foc 
ju F&60)e-ÿ%d6 = 1 
In this case it does not appear that sufficiently simple results can be 
obtained for them to be easily applied. 
3) It would also be possible to take the invariance of the function g (6) 
as a starting point, deriving the invariance of the function 8(6) as a con- 
clusion. (See ALLAIS, 1960 A, pp. 11 and 12) 
+. Allais - pag. 85