Proceedings: Mathematical, Physical and Engineering Sciences, Vol. 461, No. 2060 (Aug., 2005), pp. 2545-2562 (18 pages) The work presented here shows that the natural frequencies of constrained ...

Ray-homotheticity is proposed as a fruitful way of modelling scale economies. It permits scale economies to vary with the rate of output and the input mix, thus allowing ideal output to be input ...