The main contribution of Claes Berg's paper is to disentangle the various models in the ninth chapter of Lundberg's 1937 dissertation and to provide an explicit formulation of the equations underlying his calculations. By doing this, Berg can, in a pedagogical and convincing manner, compare Lundberg's models to those of Samuelson, Metzler, Harrod, and Domar.

It is interesting to note that this explicit spelling out of the equations also provides a clue to the explanation of why the models of the latter authors were quickly accepted in the standard economics literature, whereas those of Lundberg never found their way into the textbooks. By imposing non-negativity constraints (i.e., investment can never turn negative), the mathematical structure – which was in principle quite simple – became in practice so complicated that it only lent itself to numerical solutions. Thus the simple analytical solutions, which are necessary for models to be useful in textbooks, were lacking in Lundberg's work, although the economic insights were not.

It is refreshing to note that Berg does not argue that Lundberg “discovered” the Samuelson model of the interaction between the accelerator and the multiplier, or the Harrod-Domar model of economic growth, or the Metzler model of the inventory cycle. This seems to be a very reasonable attitude; the question of scientific priority is an intricate, and in most cases even meaningless, enterprise.