N recent years economists have worked out a considerable number of theories and concepts designed to help explain various types of economic development. These theories and concepts often overlap in analytical content and are not always clearly distinguished from each other. At this stage in research it may be useful to look for general models that encompass several theories. Such a procedure has been found helpful in the study of business cycles,' where the second-order difference equation has provided a general model of which several types of business fluctuations are special cases. Different patterns of cyclical behavior represent different ranges of parameters in the general model. This paper suggests a model -also in the form of a difference equation -which has, as special cases, some, though by no means all, theories of economic development. The model is concerned mainly with types of development that may be called in the sense that they represent relationships between two different economies or between two different sectors in an economy. As examples of dualistic theories, attention is called to a modification of the Hoselitz system of types of development, to a model of Myrdal, and, in a somewhat generalized form, to an argument of Prebisch.

Journal Article Devaluation and the Cost of Living in the United Kingdom Get access James L. Burtle, James L. Burtle Geneva, Washington Search for other works by this author on: Oxford Academic Google Scholar Wolfram Liepe Wolfram Liepe Geneva, Washington Search for other works by this author on: Oxford Academic Google Scholar The Review of Economic Studies, Volume 17, Issue 1, 1949, Pages 1–28, https://doi.org/10.2307/2295786 Published: 01 April 1949