290 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28

If I can answer to the FISHER point, I would say that the
agreement between the averages for the United States, for the world
and for 1913 (§ 321 and 323 of my paper) is in any case really
striking. Of course there are some differences but many other
factors are operating and what is astonishing is not that some small
differences exists, but that these differences are in relative terms
so small.

And finally I would add that some of the arguments I have
heard are very strange indeed. If the statistical data and my theory
were in total disagreement, nobody would have said, « Oh, it is
clear: if there is disagreement, the data are wrong ». They would
have said, and in my opinion rightly, « The theory is wrong because
it does not agree at all with the facts ». So, if there is concordance
here between the theory and the facts, we must recognise that there
is an agreement, and this is certainly a point in favour of any theory
at all times. Perhaps it could be argued that this agreement is due
co chance. I am very doubtful about such a proposition. It is
juite unbelievable that such coherence between figures for the United
States between 1880 and 1956 and for Great Britain or France in
1913 and for 58 values for 21 countries could arise bv chance.

THEIL

I am afraid that I did not succeed in making my point sufficiently
clear. What I was trying to say is that in a great many cases
economic statisticians have to face the problem that the data which
‘hey collect imply sizeable uncertainties. The uncertainty may either
be due to the inferior quality of the data themselves, or to their
imperfect relevance with respect to the variables for which they are
used, or to their sample character. When there is a large range of
uncertainty it is evidently rather arbitrary which particular point
estimate will be published. Under such circumstances it is not at all
unreasonable that other considerations are taken into account (besides
 the uncertain numerical data) when a decision has to be made

irl Allais - pag. 204