- Email: [email protected]
Spatial planning for the LDC's
Socio-Econ. Plan. Sci. Vol.16.No.4, pp. 193-194,1982 Printedin GreatBritain.
0038-0121/821040193-02503.0010
PergamonPressLtd.
NOTE SPATIAL
PLANNING
FOR THE
LDC'S
P E T E R GORDON School Urban and Regional Planning, University of Southern California, University Park, Los Angleles, CA 90007, U.S.A. l. INTRODUCTION The problems of the less developed countries are, to an increasing extent, problems of urbanization and problems associated with large cities. The U.N.[1] reports that whereas the "Less Developed Regions" of the world were 17% urbanized in 1950, that figure had risen to 28% by 1975 and is expected to reach 37% in 2000. Rising shares of the most rapidly growing populations suggest major movements from rural to urban areas. Most of the urban gains will be in the largest cities. Recent forecasts indicate that Mexico City may reach 30 million by 2000 and Cairo will approach 20 million. These and other heretofore unimagined "super cities" will have the effect of adding substantial urban management problems to the already imposing problems of economic development. The well known Todaro theory of migration points out that urbanization in the LDC's is not an equilibrating process: migration appears to feed urban unemployment and underemployment. All of these recent developments have led to a minor reassessment of the traditional growth centers model of development. Many planners now see these centers as counter-magnets to primate city growth. The secondary centers are often justified as places that could intercept and/or siphon growth from the major city. This paper does not debate the merits of a countermagnets strategy. Rather, the implementation of that sort of strategy is discussed. The lack of analysis of ways to promote counter-magnets is astonishing. Shaw [2] has correctly identified the issue and also worries that any upgrading of the largest LDC city will have the unpleasant effect of attracting new migrants, swamping any initial ameliorative effect. In the case of large city job-creation programs, the Todaro effect (the in-migrant job multiplier) predicts that for every new job created, more than one migrant appears. Shaw's prescription is a "dwelling starts" strategy whereby dwelling starts in some places ougnt to be, "modified. . . . . toward enhancing their socio-economic profile more than others . . . . " This position can be criticized as being a bit vague. How much of a relative housing shortage are planners supposed to create? Is the approach actually implementable? Is the trade-off between today's misery and tomorrow's gains handled a bit too cavalierly? A second criticism is that a far more promising strategy exists. For lack of a better term, we shall refer to our proposed strategy as "induced beaten paths." "It rests on the robust finding from many of the LDC's that rural-to-urban migration is heavily influenced by migrant stock effects. This has variously been referred to as "the beaten path effect," "friends and relatives effect," or simply migration stock elasticity.t In what follows we survey some of the evidence on migration in the LDC's. Then we discuss some ways to implement induced beaten paths. Finally, we summarize and offer some thoughts for further work.
tThe implied autoregressive process certainly does nothing to explain the transition made by the first migrants between any origin-destination pair. Yet policy, not explanation, is our main focus. eNelson[8] has also, rightly, argued that since "beaten paths" are function of past migrations, they are also a function of all the variables which could explain those flows. Thus, coefficient estimates for all these variables for any yearly flow cannot show exact current impact.
2. THE EVIDENCE
The problems of the less developed countries have taken on a major new dimension which can be called the problems of rapid urbanization. In fact, some commentators have judged that for the next several decades, "urban problems" will be mainly a third world phenomenon (Renaud[3D. Urban population growth rates in many of the LDC's will soon reach several times the rates of population growth of tl~ rural areas, resulting in: (1) almost half of the LDC's populations living in the cities; (2) unprecedented city sizes; (3) many cities gaining as many as one-half million new residents each year. In 1950 about 20% of LDC populations lived in urban areas. In 1975 the proportion was 31%. The World Bank expects it to reach 45% by 2000. Linn[4] reports that, "This rapid urbanization process has been accompanied by explosive growth of the large cities. For example, in the mid-1970s Mexico City and Sap Paulo each grew by over half a million people annually, while such cities as Jarkarta and Seoul grew by over a quarter of a million people each year . . . . By their very size, such metropolises.., are in the same league as the medium size and large developing countries . . . . In 1976, 35 of the 92 developing countries had less than five million inhabitants, and 54 had less than 10 million inhabitants." The author's own recent investigations suggest that Greater Cairo may add as many as one half-million inhabitants in each year of the 1990s. Several forecasters have suggested that Mexico City will reach 30,000,000 by 2000! Many have invoked the concept of "overurbanization" to describe these cases. While the futility of the "optimal city size" controversy is now widely recognized, there is considerable disagreement on efficient rates of city growth (Kelley and Williamson[5]). Because of obvious bottlenecks, it is likely that city administrators in the LDC's will soon have to worry about unprecedented yearly additions to resource and social systems requirements; they must do all this while trying to upgrade social services to those urban poor who are already present in large numbers. Another way to put it is to note that the largest cities of the LDC's often contain some of the worst poverty and are, rightly, the object of policies aimed at alleviating sorrowful conditions; insofar as these improvements are successful, they attract evermore migrants. In fact, the hypothesis of Todaro [6] suggests that there is a substantial in-migration multiplier attached to new city jobs. What we have, then, may be another equity vs efficiency trade-off: as we try to alleviate poverty in the large cities, we draw new migrants to these large cities whose numbers either drown the initial effort or create a number of new economic problems. What is the way out? If any sort of decentralization policy is adopted, how can it be made to work? One response which has long been apparent, but which to our knowledge is surprisingly absent from the literature on urbanization in the LDC's, is based on the large amount of finished research on rural-to-urban migration. These studies have uncovered a remarkable consistency in migration behavior. Namely, migratory flows are in large part responsive to stocks of former migrants at the destination. Rural-to-urban migrants' behavior, following predecessor migrants over the same path, has widely been interpreted as an attempt to economize on information costs or to minimize uncertainty (not just economic). Support for this interpretation comes from the fact that regression weights on the distance effect usually fall drastically as soon as the migrant stock variable is added. In other words, distance's reflection of information cost is reduced by this other information cost variable.:~ 193
194
Note
A recent study of Mexican migration (Gordon and Tbeobald[7]) has revealed that the migrant stock elasticity was roughly 0.83, that it drastically reduced all other elasticities when included in a log-linear regression, leaving only distance as another significant explanatory variable. Migrant stock reduced the effect of distance in a large enough way to suggest that in the absence of migrant stock, distance picks up most of the information barriers which we expect migrants to face. Levy and Wadycki[9] report almost the same results for Venezuela. In their investigation, the migrant stock elasticity was 0.63 when other effects were controlled for. It also reduced the other elasticities once it entered the equation, leaving few of them significant. The distance elasticity fell (in absolute value) from -1.212 to -0.302. Only education retained a higher absolute value coefficient than migrant stock (excluding income which had the wrong sign). Using the same model for the case of India, Greenwood[10] reports similar findings again. There, the migrant stock elasticity is 0.75 and also has the highest absolute value coefficient (of those variables whose coefficients have the proper sign). Many investigators have found this effect to hold in the U.S. (Rubin [ l l ], Morrison[12] Greenwood[B], to name just some). We do not want to extend the scope of this discussmn to include any of the DC's, yet it is interesting to note that the empirical story is the same there too. Greenwood's[14] migrant stock elasticity for the U.S. is 0.521, a similar magnitude as in the LDC studies. Walsh[15] finds that almost the same is true for Ireland. In another LDC study, Greenwood[16] looks at internal migration in Egypt and finds indirect support for the beaten path effect. This is because his dependent variable is not a standard annual migrant flow variable, but rather the stock of migrants, which he uses as a proxy for recent flows. He interprets the significance of origin and densitation populations as explanatory variables, claiming that, "the greater the population of either region i or region ./, the greater is the number of persons born in region i and living in region j, the more information that is likely to be channeled from region ] back to region i." Similar indirect evidence on behalf of the migration stock elasticity is reported by Moreland[17] who deals with a cross section of 39 LDC's. Moreland finds that, in predicting rural-tourban migration, the ratio of agricultural to total population is highly significant, with the expected negative sign.t Other studies indirectly corroborate this result J: In the cited papers, the consistency of the strength of the beaten path effect is striking and must no.: go unnoticed to policy analysts concerned with overurbanization. It is surely a stronger empirical base for a policy recommendation than that cited by Shaw on behalf of the dwelling starts strategy. 3. IMPLEMENTATION If recent migrants to the largest city were induced to move to the counter-magnet, two powerful forces would be set in motion: information would be sent hack to the largest city and to the rural origins. Thus, several information barriers facing prospective migrants visa vis the counter-magnet would be diminished. It might even be made to grow at the expense of the largest city. Just how migrants can be induced to make this second move will often depend on local circumstances. It is here that the secondary findings of the cited migration studies become important: transportation subsidies, guaranteed employment, or guaranteed housing could be offered to the proper individuals. What is of interest is that, in terms of an induced beaten paths policy, these three incentives become necessary conditions
tMoreland utilizes a rural-urban partition and an agriculturenonagriculture partition almost interchangeably, citing various forms of the available data as making this necessary. :~Beals, Levy and Moses[18] omit migrant stock but find distance to be highly significant in their Ghana study. They admit that, "distance serves as a proxy for omitted variables as well as a measure of transfer cost." Also, their highly significant origin and destination population variables could be interpreted as in Green~ood's Egypt study,
which are, by themselves, not sufficient unless the proper information flows are induced and the proper populations targeted. The implied policy, then, reduces to actually targeting the pull factors to those who have recently entered the largest city. A significant migrant "stock elasticity" will exist only if an area's in-migrants hail from a few sources, as opposed to a large number of origins. The induced beaten paths policy is easier to implement in the former instance. 4. SUMMARY We have cited evidence which shows that a large and significantly positive migrant stock elasticity is much more than an occasional finding. It is often the largest elasticity of migration flow and is found with remarkable consistency throughout migration studies of the LDC's. In fact, it dwarfs (often wipes out) other effects. The policy prescription which emerges is, then, quite obvious. The relative strengths of the various push and pull factors must be continued to be sorted out. Yet, once discovered, they should be the basis of policies which not only foster attractive opportunities at appropriately chosen destinations, but which also assign eligibility for these to specific target groups, those who have recently moved to the largest city. REFERENCES
1. United Nations Population Division, Patterns of Urban and Rural Population Growth (1980). 2. R. P. Shaw, On modifying metropolitan migration. Economic Development and Cultural Change (1978). 3. B. Renaud, National urbanization policies in developing countries. The World Bank (1979). 4. J. F. Linn, Policies/or E~icient and Equitable Growth of Cities in Developing Countries. World Bank Staff Working Paper No. 342 (1979). 5. A. Kelley, and J. Williamson. Modeling, Urbanization and Economic Growth IIASA, Laxenburg, Austria, WP-79 (1981). 6. M. P. Todaro, A model of labor migration and urban unemployment in less developed countries. Am. Econ. Rev. 59, 138-148 (1969). 7. P. Gordon and P. M. Theobald. Migration and spatial development in the Republic of Mexico. J. Dee. Areas (forthcoming). 8. P. Nelson, Migration, real income and information. J. Reg. Sci. 1, 43-74 (1959). 9. M. B. Levy and W. J. Wadycld. The influence of family and friends on geographci labor mobility: an international comparison. Rev. Econ. Stat. $$, 198-203 (1973). 10. M. J. Greenwood, The influence of family and friends on geographic labor mobility in a less-developed country: the case of India. Rev. Reg. Studies 3, 27-36, (1973). 1I. M. Rubin, Migration patterns of negroes from a rural northeastern Mississippi community. Social Forces 39, 59-67 (1960). 12. P. A. Morrison, A demographic assessment of new cities and growth centers; population redistribution strategies. Public Policy 3, 367-382 (1973). 13. M. J. Greenwood, An analysis of the determinants of geographic mobility in the United States. The Rev. Econ. Stat. 51, 189-194 (1969). 14. M. J. Greenwood, Lagged response in the decision to migrate. J. Reg. Sci. 10, 375-384 (1970). 15. B. M. Walsh, Expectations, information and human migration: specifying an econometric model of Irish migration of Britain. J. Reg. Sci. 14, 107-120 (1974). 16. M. J. Greenwood, The determinants of labor migration in Egypt. J. Reg. Sci. 9, 283-290 (1969). 17. R. S. Moreland, Population, internal migration and economic growth: an empirical analysis, Warwick Econ. Res. Papers, No. 158 (1979). 18. R. E. Beals and M. B. Levy and L. N. Moses, Rationality and migration in Ghana. Rev. Econ. Stat. 49, 480-486 (1967). 19. G. S. Sahota, An economic analysis of internal migration in Brazil. J. Pol. Econ. 76, 218-245 (1968).
0038-0121/821040193-02503.0010
PergamonPressLtd.
NOTE SPATIAL
PLANNING
FOR THE
LDC'S
P E T E R GORDON School Urban and Regional Planning, University of Southern California, University Park, Los Angleles, CA 90007, U.S.A. l. INTRODUCTION The problems of the less developed countries are, to an increasing extent, problems of urbanization and problems associated with large cities. The U.N.[1] reports that whereas the "Less Developed Regions" of the world were 17% urbanized in 1950, that figure had risen to 28% by 1975 and is expected to reach 37% in 2000. Rising shares of the most rapidly growing populations suggest major movements from rural to urban areas. Most of the urban gains will be in the largest cities. Recent forecasts indicate that Mexico City may reach 30 million by 2000 and Cairo will approach 20 million. These and other heretofore unimagined "super cities" will have the effect of adding substantial urban management problems to the already imposing problems of economic development. The well known Todaro theory of migration points out that urbanization in the LDC's is not an equilibrating process: migration appears to feed urban unemployment and underemployment. All of these recent developments have led to a minor reassessment of the traditional growth centers model of development. Many planners now see these centers as counter-magnets to primate city growth. The secondary centers are often justified as places that could intercept and/or siphon growth from the major city. This paper does not debate the merits of a countermagnets strategy. Rather, the implementation of that sort of strategy is discussed. The lack of analysis of ways to promote counter-magnets is astonishing. Shaw [2] has correctly identified the issue and also worries that any upgrading of the largest LDC city will have the unpleasant effect of attracting new migrants, swamping any initial ameliorative effect. In the case of large city job-creation programs, the Todaro effect (the in-migrant job multiplier) predicts that for every new job created, more than one migrant appears. Shaw's prescription is a "dwelling starts" strategy whereby dwelling starts in some places ougnt to be, "modified. . . . . toward enhancing their socio-economic profile more than others . . . . " This position can be criticized as being a bit vague. How much of a relative housing shortage are planners supposed to create? Is the approach actually implementable? Is the trade-off between today's misery and tomorrow's gains handled a bit too cavalierly? A second criticism is that a far more promising strategy exists. For lack of a better term, we shall refer to our proposed strategy as "induced beaten paths." "It rests on the robust finding from many of the LDC's that rural-to-urban migration is heavily influenced by migrant stock effects. This has variously been referred to as "the beaten path effect," "friends and relatives effect," or simply migration stock elasticity.t In what follows we survey some of the evidence on migration in the LDC's. Then we discuss some ways to implement induced beaten paths. Finally, we summarize and offer some thoughts for further work.
tThe implied autoregressive process certainly does nothing to explain the transition made by the first migrants between any origin-destination pair. Yet policy, not explanation, is our main focus. eNelson[8] has also, rightly, argued that since "beaten paths" are function of past migrations, they are also a function of all the variables which could explain those flows. Thus, coefficient estimates for all these variables for any yearly flow cannot show exact current impact.
2. THE EVIDENCE
The problems of the less developed countries have taken on a major new dimension which can be called the problems of rapid urbanization. In fact, some commentators have judged that for the next several decades, "urban problems" will be mainly a third world phenomenon (Renaud[3D. Urban population growth rates in many of the LDC's will soon reach several times the rates of population growth of tl~ rural areas, resulting in: (1) almost half of the LDC's populations living in the cities; (2) unprecedented city sizes; (3) many cities gaining as many as one-half million new residents each year. In 1950 about 20% of LDC populations lived in urban areas. In 1975 the proportion was 31%. The World Bank expects it to reach 45% by 2000. Linn[4] reports that, "This rapid urbanization process has been accompanied by explosive growth of the large cities. For example, in the mid-1970s Mexico City and Sap Paulo each grew by over half a million people annually, while such cities as Jarkarta and Seoul grew by over a quarter of a million people each year . . . . By their very size, such metropolises.., are in the same league as the medium size and large developing countries . . . . In 1976, 35 of the 92 developing countries had less than five million inhabitants, and 54 had less than 10 million inhabitants." The author's own recent investigations suggest that Greater Cairo may add as many as one half-million inhabitants in each year of the 1990s. Several forecasters have suggested that Mexico City will reach 30,000,000 by 2000! Many have invoked the concept of "overurbanization" to describe these cases. While the futility of the "optimal city size" controversy is now widely recognized, there is considerable disagreement on efficient rates of city growth (Kelley and Williamson[5]). Because of obvious bottlenecks, it is likely that city administrators in the LDC's will soon have to worry about unprecedented yearly additions to resource and social systems requirements; they must do all this while trying to upgrade social services to those urban poor who are already present in large numbers. Another way to put it is to note that the largest cities of the LDC's often contain some of the worst poverty and are, rightly, the object of policies aimed at alleviating sorrowful conditions; insofar as these improvements are successful, they attract evermore migrants. In fact, the hypothesis of Todaro [6] suggests that there is a substantial in-migration multiplier attached to new city jobs. What we have, then, may be another equity vs efficiency trade-off: as we try to alleviate poverty in the large cities, we draw new migrants to these large cities whose numbers either drown the initial effort or create a number of new economic problems. What is the way out? If any sort of decentralization policy is adopted, how can it be made to work? One response which has long been apparent, but which to our knowledge is surprisingly absent from the literature on urbanization in the LDC's, is based on the large amount of finished research on rural-to-urban migration. These studies have uncovered a remarkable consistency in migration behavior. Namely, migratory flows are in large part responsive to stocks of former migrants at the destination. Rural-to-urban migrants' behavior, following predecessor migrants over the same path, has widely been interpreted as an attempt to economize on information costs or to minimize uncertainty (not just economic). Support for this interpretation comes from the fact that regression weights on the distance effect usually fall drastically as soon as the migrant stock variable is added. In other words, distance's reflection of information cost is reduced by this other information cost variable.:~ 193
194
Note
A recent study of Mexican migration (Gordon and Tbeobald[7]) has revealed that the migrant stock elasticity was roughly 0.83, that it drastically reduced all other elasticities when included in a log-linear regression, leaving only distance as another significant explanatory variable. Migrant stock reduced the effect of distance in a large enough way to suggest that in the absence of migrant stock, distance picks up most of the information barriers which we expect migrants to face. Levy and Wadycki[9] report almost the same results for Venezuela. In their investigation, the migrant stock elasticity was 0.63 when other effects were controlled for. It also reduced the other elasticities once it entered the equation, leaving few of them significant. The distance elasticity fell (in absolute value) from -1.212 to -0.302. Only education retained a higher absolute value coefficient than migrant stock (excluding income which had the wrong sign). Using the same model for the case of India, Greenwood[10] reports similar findings again. There, the migrant stock elasticity is 0.75 and also has the highest absolute value coefficient (of those variables whose coefficients have the proper sign). Many investigators have found this effect to hold in the U.S. (Rubin [ l l ], Morrison[12] Greenwood[B], to name just some). We do not want to extend the scope of this discussmn to include any of the DC's, yet it is interesting to note that the empirical story is the same there too. Greenwood's[14] migrant stock elasticity for the U.S. is 0.521, a similar magnitude as in the LDC studies. Walsh[15] finds that almost the same is true for Ireland. In another LDC study, Greenwood[16] looks at internal migration in Egypt and finds indirect support for the beaten path effect. This is because his dependent variable is not a standard annual migrant flow variable, but rather the stock of migrants, which he uses as a proxy for recent flows. He interprets the significance of origin and densitation populations as explanatory variables, claiming that, "the greater the population of either region i or region ./, the greater is the number of persons born in region i and living in region j, the more information that is likely to be channeled from region ] back to region i." Similar indirect evidence on behalf of the migration stock elasticity is reported by Moreland[17] who deals with a cross section of 39 LDC's. Moreland finds that, in predicting rural-tourban migration, the ratio of agricultural to total population is highly significant, with the expected negative sign.t Other studies indirectly corroborate this result J: In the cited papers, the consistency of the strength of the beaten path effect is striking and must no.: go unnoticed to policy analysts concerned with overurbanization. It is surely a stronger empirical base for a policy recommendation than that cited by Shaw on behalf of the dwelling starts strategy. 3. IMPLEMENTATION If recent migrants to the largest city were induced to move to the counter-magnet, two powerful forces would be set in motion: information would be sent hack to the largest city and to the rural origins. Thus, several information barriers facing prospective migrants visa vis the counter-magnet would be diminished. It might even be made to grow at the expense of the largest city. Just how migrants can be induced to make this second move will often depend on local circumstances. It is here that the secondary findings of the cited migration studies become important: transportation subsidies, guaranteed employment, or guaranteed housing could be offered to the proper individuals. What is of interest is that, in terms of an induced beaten paths policy, these three incentives become necessary conditions
tMoreland utilizes a rural-urban partition and an agriculturenonagriculture partition almost interchangeably, citing various forms of the available data as making this necessary. :~Beals, Levy and Moses[18] omit migrant stock but find distance to be highly significant in their Ghana study. They admit that, "distance serves as a proxy for omitted variables as well as a measure of transfer cost." Also, their highly significant origin and destination population variables could be interpreted as in Green~ood's Egypt study,
which are, by themselves, not sufficient unless the proper information flows are induced and the proper populations targeted. The implied policy, then, reduces to actually targeting the pull factors to those who have recently entered the largest city. A significant migrant "stock elasticity" will exist only if an area's in-migrants hail from a few sources, as opposed to a large number of origins. The induced beaten paths policy is easier to implement in the former instance. 4. SUMMARY We have cited evidence which shows that a large and significantly positive migrant stock elasticity is much more than an occasional finding. It is often the largest elasticity of migration flow and is found with remarkable consistency throughout migration studies of the LDC's. In fact, it dwarfs (often wipes out) other effects. The policy prescription which emerges is, then, quite obvious. The relative strengths of the various push and pull factors must be continued to be sorted out. Yet, once discovered, they should be the basis of policies which not only foster attractive opportunities at appropriately chosen destinations, but which also assign eligibility for these to specific target groups, those who have recently moved to the largest city. REFERENCES
1. United Nations Population Division, Patterns of Urban and Rural Population Growth (1980). 2. R. P. Shaw, On modifying metropolitan migration. Economic Development and Cultural Change (1978). 3. B. Renaud, National urbanization policies in developing countries. The World Bank (1979). 4. J. F. Linn, Policies/or E~icient and Equitable Growth of Cities in Developing Countries. World Bank Staff Working Paper No. 342 (1979). 5. A. Kelley, and J. Williamson. Modeling, Urbanization and Economic Growth IIASA, Laxenburg, Austria, WP-79 (1981). 6. M. P. Todaro, A model of labor migration and urban unemployment in less developed countries. Am. Econ. Rev. 59, 138-148 (1969). 7. P. Gordon and P. M. Theobald. Migration and spatial development in the Republic of Mexico. J. Dee. Areas (forthcoming). 8. P. Nelson, Migration, real income and information. J. Reg. Sci. 1, 43-74 (1959). 9. M. B. Levy and W. J. Wadycld. The influence of family and friends on geographci labor mobility: an international comparison. Rev. Econ. Stat. $$, 198-203 (1973). 10. M. J. Greenwood, The influence of family and friends on geographic labor mobility in a less-developed country: the case of India. Rev. Reg. Studies 3, 27-36, (1973). 1I. M. Rubin, Migration patterns of negroes from a rural northeastern Mississippi community. Social Forces 39, 59-67 (1960). 12. P. A. Morrison, A demographic assessment of new cities and growth centers; population redistribution strategies. Public Policy 3, 367-382 (1973). 13. M. J. Greenwood, An analysis of the determinants of geographic mobility in the United States. The Rev. Econ. Stat. 51, 189-194 (1969). 14. M. J. Greenwood, Lagged response in the decision to migrate. J. Reg. Sci. 10, 375-384 (1970). 15. B. M. Walsh, Expectations, information and human migration: specifying an econometric model of Irish migration of Britain. J. Reg. Sci. 14, 107-120 (1974). 16. M. J. Greenwood, The determinants of labor migration in Egypt. J. Reg. Sci. 9, 283-290 (1969). 17. R. S. Moreland, Population, internal migration and economic growth: an empirical analysis, Warwick Econ. Res. Papers, No. 158 (1979). 18. R. E. Beals and M. B. Levy and L. N. Moses, Rationality and migration in Ghana. Rev. Econ. Stat. 49, 480-486 (1967). 19. G. S. Sahota, An economic analysis of internal migration in Brazil. J. Pol. Econ. 76, 218-245 (1968).