The models Feldstein and Rothschild, on the hand, and Jorgenson on the other adopted in 1974 to highlight the replacement ratio are identical. Yet, the authors reached opposite conclusions and the latter's view prevailed, which is weaker in terms of theoretical and empirical foundations. This...

This paper investigates the effects of uncertainty emanating from technological im-provements on the optimal lifetime of assets. In does so in a dynamic model in which: a) technological change increases continuously the productivity of producers’ durables, b) po-tential competition induces...

This paper analyzes and compares two alternative policies of determining the service life and replacement demand for vintage equipment under embodied technological change. The policies are the infinite-horizon replacement and the transitory replacement ending with scrapping. The corresponding...

It is ascertained that the theorem of proportionality, which maintains that replacement investment is a constant proportion of the outstanding capital stock, has several fundamental shortcomings. It derives from a model founded on assumptions that are highly restrictive and unlikely to hold in...

Our objective in this paper is to shed light on the economic forces and the specific way in which they combine to determine the service life, and hence the replacement demand for durables, in the short run and in the long run. For this purpose the received multiperiod economic replacement model...

This paper surveys and assesses the empirical literature that bears on the applicability of the theorem of proportionality, which asserts that depreciation is proportional to the outstanding capital stock. All available evidence shows that: a) the rates of depreciation and retirements vary from...