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tion system (!). The latter perhaps corresponds better than
the former to the approach taken in the present work, but the
former has had in practice wider empirical applications. There-
fore, it will be convenient here to take LEONTIEF’s system as
the static term of our comparisons.
First of all, let me point out the similarity of approach,
from an empirical point of view, of the previous dynamic mo-
del and the static input-output model. Both models share the
characteristic of being built on coefficients which represent
actual outcomes and which can, therefore, at least in principle,
be given an empirical content simply by recording the actual
performance of the economic system. Of course, the technical
and the consumption coefficients, by which this actual perform-
ance is represented, come from a choice, made from among a
larger set of possibilities. But all the alternative possibilities
that might have, but have not, been chosen have become irre-
levant. The coefficients that appear both in the input-output
and in the present model must, therefore, be interpreted as
simply representing those real quantities which can actually be
observed.
Let us notice, moreover that LEONTIEF’s system and the
present model also coincide in the way they look at the final
sector of the economy — the last column of the coefficient
matrices are the same in the two systems (with the only dif-
ference that, in the present model, consumption goods and
investment goods are listed separately). However, they differ
profoundly in the way they consider the production processes.
The same production structure of the economy is looked at
from two different points of view — one is very close to it and
to what is immediately observable; the other is placed much
further away, at the final stage of the consumption and invest-
ment goods. The T.LEONTIEF approach can certainly be more
(') Wassiry W. LEONTIEF, The Structure of American Economy, 1919-
1939, New York, 1941 and 1951; PIERO SRAFFA. Production of Commodities
by means of Commodities. Cambridge. 1060
[10] Pasinetti - pag. 06
