Rural-Urban Migration, Urbanization, and Economic Development

This paper presents an analytical expression of the rural net outmigration rate compatible with a logistic evolution of the part of the population that is urban in a rural-urban population system. The formula obtained represents a function consistent with the mobility revolution hypothesis of Zelinsky (1971): the rural net migration rate first increases, then passes through a maximum, and finally decreases toward zero. In addition, such a formula is used to determine the dates at which, in selected developing countries, the rural net outmigration rate will start to decline; and to estimate the degree of economic development beyond which the rural net outmigration rate levels off

Calibrating Alonso's General Theory of Movement: the Case of Inter-Provincial Migration Flows in Canada

First, it is shown that Alonso's general theory of movement relies on a standard doubly-constrained spatial interaction model which subsumes the usual gravity and entropy-derived formulations. Such a finding then suggests the use of a biproportional adjustment method (RAS method) to adequately estimate the systemic variables specified in the underlying model. This eventually leads to the development of a complete and precise methodology for calibrating the Alonso model. This methodology is illustrated with the help of an application to data on interprovincial migration in Canada

The Forces of Urbanization under Varying Natural Increase and Migration Rates

This paper is the third and last of a series seeking to shed some light on the question of whether a nation's urban population grows mostly by rural-urban migration or by natural increase. Again, the discussion evolves around an analytical study of the Keyfitz model of urbanization (Keyfitz, 1978) and the Rogers components-of-change model (Rogers, 1968) applied to a rural-urban system. Here, in contrast to the preceding papers in which rates of natural increase and migration were constant, the present paper allows these rates to vary. A larger part of the analysis is based on the Keyfitz model, shown earlier to be less meaningful than the alternative model but lending itself to an easier tractability when rates are allowed to vary. In particular, the Keyfitz model is used in an attempt to connect the variations of rural-urban (net) migration rates to economic changes through a simple scheme of wage differentials, later supplemented by the Todaro hypothesis

Constructing Multiregional Life Tables using Place-of-Birth-Specific Migration Data

The usual approach to the construction of a multiregional life table involves the calculation of a multiradix increment-decrement life table based on commonly available data about interregional migration streams. However, if the migration data are cross-classified by place of birth, an alternative multiregional life table can be obtained by constructing a set of uniradix increment-decrement life tables, calculated separately for each regional share of the initial cohort. This paper demonstrates this alternative method (place-of-birth-dependent approach) and contrasts it with the more traditional one (place-of-birth-independent approach) using data on the female population, observed between 1965 and 1970, for the system of the four US Census Regions. The main result is that the consideration of place-of-birth-specific migration data reduces somewhat the fraction of the regional expectation of life at birth to be spent outside the region of birth

The Factors and Magnitude of Urbanization under Unchanged Natural Increase and Migration Patterns

This paper is the second of a series intended to shed some light on the urbanization phenomenon. Its main purpose is to contrast the results provided by two alternative models--the model proposed by Keyfitz (1978) and the continuous version of the multiregional model of population growth and distribution developed by Rogers (1968)--under constant regimes of natural increase and migration. In both cases, the evolution of the magnitude of urbanization as well as that of the relative importance of natural increase and migration in accounting for urban growth are examined. A particular emphasis is placed on the time spans necessary to reach two cross-over points| the point at which natural increase starts exceeding in-migration in the urban region (cross-over point of type I) and the point at which the urban population becomes larger than the rural population (cross-over point of type II). The contrast between the alternative models is illustrated with the help of an application to two actual rural-urban population systems presenting polar characteristics| those of the USSR and India

Intrinsic Rates and Stable Age-Specific Mortality (and Migration) Rates of Growth Matrix Operator in Single Region (Multiregion) Population Model

This paper attempts to characterize the schedule of demographic events embodied in the stable state of single-region and multiregion models of population projection. The focus is on the age-specific mortality (migration) rates that reach, at stability, limiting values slightly different from their initial ones. Formulas giving the stable age-specific death (and migration) rates are provided as well as an indication of the discrepancy between initial and stable rates. Also, a direct calculation method for the computation of intrinsic rates relating to each demographic event is developed. Finally, in the multiregion case, the stable migration rates are compared to those derived earlier by Stone

Multiregional Population Projections

This paper is an exposition of the mathematics of multiregional population projection. We begin by outlining the notion of a multiregional life table. Next, we show how the stationary regional populations of such a life table serve as inputs to numerical calculations carried out with the multiregional versions of the discrete and continuous models of demographic growth. We then conclude with a brief consideration of some of the spatial consequences of zero population growth

Choices in the Construction of Multiregional Life Tables

The methods of multiregional life table construction are explored through an investigation of a tree of choices with respect to approach, data, rates definition, probability definition, and stationary population or life-years-lived calculation. Two principal approaches are discussed: the movement approach and the transition approach, although a third label "hybrid approach" is used to characterize many of the developments in the field to date. Methods are applied to two population systems, that of the Netherlands, where moves data are available, and that of Great Britain, where the data on migration come in the transition form. The discussion of methods and the computer runs of the life table model lead to a clear set of recommended choices for the would-be life table constructor. The fairly simple and direct transition approach using migrant data measured by a five-year question is our preferred choice. The paper ends by speculating on how solutions to the unresolved problems of multiregional population analysis might be sought

A Demoeconomic Model of Interregional Growth Rate Differences

This paper sets forth a demoeconomic approach to interregional development along non-neoclassical lines. This objective is carried out by elaborating on a recently published model of interregional growth rate differences (Dixon and Thirlwall, 1975). First, a critical review of this model suggests the implausibility of its main result, i.e., the possibility of steady growth by a pair of regions over the long run. It is shown that (a) the omission of migration which would eventually dampen the implied income divergence; and (b) the linear structure of the model cause such a result. Thus, an extension of this model is proposed which includes migration as well as other demographic aspects of development (labor force participation and unemployment), endogenously and simultaneously determined. Interestingly enough, the nature of these variables provides an impetus for reconsidering linearity| the proper modeling of demoeconomic effects necessarily introduces non- linearities. Non-static long-term rates of change are shown to emerge from the simulation of this extended model| as a consequence of population shifts due to migration, there appear regional cycles accompanied by cycles of divergence and convergence of income

Increment-Decrement Life Tables: A Comment

In a recent paper, R. Schoen poses the problem of constructing a set of k interrelated increment-decrement life tables but presents explicit solutions only for two-table and three-table models. Here, we derive the k-table analogue of the single-table formula (Schoen's Eq. 11) and illustrate its use in a problem area not included in Schoen's list of potential applications, namely, multiregional life table construction. In this particular application, increments are due to in-migration and decrements result from out-migration