The Implications of Alternative Saving and Expectations Hypotheses for Choices of Technique and Patterns of Growth

摘要: It has become increasingly clear that there are serious problems with the concept of aggregate capital. is now known, for instance, that, if many vintages machines, output economy can be described by a simple neoclassical production function an capital stock and only technical change purely augmenting (Fisher, 1965); in steady states consumption per capita may not monotonic rate interest, even rates interest greater than growth; value man (using any price system) r (Wicksell effects) (Champernowne, 1953-54). The heterogeneity goods, moreover, raises new dynamic behavior economy. Investment must allocated, to do this firms form expectations future prices, wages, rates. purpose paper investigate detail dynamics model heterogeneous goods under alternative assumptions about formation saving. Before investment takes place, entrepreneur choice over large number (to precise, continuum) types machines; those which require more resources today less labor unit future. But once machine been constructed, it cannot altered. This just exante smooth substitutability-ex post rigid complementarity (or putty-clay model), versions have studied Johansen (1959) Solow (1962). (See also Phelps, 1963; Akerlof, 1967; Sheshinski, Stiglitz, 1968.) raises, interesting problem economic obsolescence: machines con-