SEMAINE D ETUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIOUE ETC. 
08G 
tain that the estimates we have now are very questionable. But 20 
or 30 years ago the same was true for national income figures and 
many people were saying at that time that this sort of calculation 
was useless and had no meaning at all, and so on. 
My second point. What Professor THEIL has said is very interest- 
ing indeed, as far as the proposal for some general statement con- 
cluding this colloquium is concerned. I have read in the introduction 
to the Study Week that econometrics has made much progress and 
so on, and to-day we hear from a very competent colleague that 
the work of every statistician in the world may after all be very 
questionable, not only from the scientific point of view but from 
the point of view of honesty. What you have said is terrible indeed. 
Terrible. For if you were right, this would mean that statisticians 
are dishonest. Personally I do not accept this point. I believe that 
statisticians do not revise their estimates when they differ from 
other estimates, and I can supply very good proof of it. For exam- 
ple, there are differences between the various estimates CoLIN CLARK 
has given for the capital output ratios of different countries at 
different times. These estimates are indeed very different from one 
country to another and from one time to another. As you know, 
CoLIN CLARK has not made any personal calculations on this. The 
figures published by him are estimates made by different statisticians 
around the world, using very different methods and taking into 
account statistical materials which are absolutely not comparable. 
Not only are these figures not the same, but their order of magnitude 
is absolutely different. We therefore cannot suspect the statisticians 
of having modified their estimates in order to be in agreement witl. 
the other evaluations. The contrary is the case. 
But if these figures are absolutely different, they are distributed 
lognormally and their median is practically the same as median for 
the United States from 1880 to 1956. Thus we can conclude that 
there is an unquestionable reality behind these very different esti- 
mates and we can conclude that the differences are due to some 
random influences 
1 Allais - pag. 293