Stochastic Forecasting of Labor Supply and Population: An Integrated Model

This paper presents a stochastic model to forecast the German population and labor supply until 2060. Within a cohort-component approach, our population forecast applies principal components analysis to birth, mortality, emigration, and immigration rates, which allows for the reduction of dimensionality and accounts for correlation of the rates. Labor force participation rates are estimated by means of an econometric time series approach. All time series are forecast by stochastic simulation using the bootstrap method. As our model also distinguishes between German and foreign nationals, different developments in fertility, migration, and labor participation could be predicted. The results show that even rising birth rates and high levels of immigration cannot break the basic demographic trend in the long run. An important finding from an endogenous modeling of emigration rates is that high net migration in the long run will be difficult to achieve. Our stochastic perspective suggests therefore a high probability of substantially decreasing the labor supply in Germany.     

Three strikes and you're out: Demographic analysis of mandatory prison sentencing

Much of the debate about the costs and benefits of “three-strikes” laws for repeat felony offenders is implicitly demographic, relying on unexamined assumptions about prison population dynamics. However, even state-of-the-art analysis has omitted important demographic details. We construct a multistate life-table model of population flows to and from prisons, incorporating age-specific transition rates estimated from administrative data from Florida. We use the multistate life-table model to investigate patterns of prison population growth and aging under many variants of three-strikes laws. Our analysis allows us to quantify these demographic changes and suggests that the aging of prison populations under three-strikes policies will Significantly undermine their long-run effectiveness.     

Macro‐demographic effects of the transition to adulthood: Multistate stable population theory and an application to Italy

We exploit a multistate generalisation of a classical, one‐sex, stable population model to evaluate structural and long‐term effects of changes in the attainment of adulthood. The demographic framework that inspired this paper is provided by Italy, where a strong delay in the transition to adulthood and union formation has been observed over the last several decades. Italy has also experienced very low fertility levels, and the subsequent ageing problems have become of primary concern. We first discuss a theoretical framework based on the model developed by Inaba (1995) and then include the process of transition to adulthood. We consider explicitly some specifications of the general model, and we present two distinct empirical applications, one using macrosimulation and the other one using a linear approximation. Our principal aim is to evaluate the impact of the delay in the attainment of adulthood on reproduction and on the age structure of the population.     

Emigration Rates From Sample Surveys: An Application to Senegal

What is the emigration rate of a country, and how reliable is that figure? Answering these questions is not at all straightforward. Most data on international migration are census data on foreign-born population. These migrant stock data describe the immigrant population in destination countries but offer limited information on the rate at which people leave their country of origin. The emigration rate depends on the number leaving in a given period and the population at risk of leaving, weighted by the duration at risk. Emigration surveys provide a useful data source for estimating emigration rates, provided that the estimation method accounts for sample design. In this study, emigration rates and confidence intervals are estimated from a sample survey of households in the Dakar region in Senegal, which was part of the Migration between Africa and Europe survey. The sample was a stratified two-stage sample with oversampling of households with members abroad or return migrants. A combination of methods of survival analysis (time-to-event data) and replication variance estimation (bootstrapping) yields emigration rates and design-consistent confidence intervals that are representative for the study population.     

Compulsory Schooling Laws and Migration Across European Countries

Educational attainment is a key factor for understanding why some individuals migrate and others do not. Compulsory schooling laws, which determine an individual’s minimum level of education, can potentially affect migration. We test whether and how increasing the length of compulsory schooling influences migration of affected cohorts across European countries, a context where labor mobility is essentially free. We construct a novel database that includes information for 31 European countries on compulsory education reforms passed between 1950 and 1990. Combining this data with information on recent migration flows by cohorts, we find that an additional year of compulsory education reduces the number of individuals from affected cohorts who migrate in a given year by 9 %. Our results rely on the exogeneity of compulsory schooling laws. A variety of empirical tests indicate that European legislators did not pass compulsory education reforms as a reaction to changes in emigration rates or educational attainment.     

Migrant Networks and International Migration: Testing Weak Ties

This article examines the role of migrant social networks in international migration and extends prior research by testing the strength of tie theory, decomposing networks by sources and resources, and disentangling network effects from complementary explanations. Nearly all previous empirical research has ignored friendship ties and has largely neglected extended-family ties. Using longitudinal data from the Migration between Africa and Europe project collected in Africa (Senegal) and Europe (France, Italy, and Spain), this article tests the robustness of network theory—and in particular, the role of weak ties—on first-time migration between Senegal and Europe. Discrete-time hazard model results confirm that weak ties are important and that network influences appear to be gendered, but they do not uphold the contention in previous literature that strong ties are more important than weak ties for male and female migration. Indeed, weak ties play an especially important role in male migration. In terms of network resources, having more resources as a result of strong ties appears to dampen overall migration, while having more resources as a result of weaker ties appears to stimulate male migration. Finally, the diversity of resources has varied effects for male and female migration.     

Probabilistic population projections for countries with generalized HIV/AIDS epidemics

In 2015, the United Nations (UN) issued probabilistic population projections for all countries up to 2100, by simulating future levels of total fertility and life expectancy and combining the results using a standard cohort component projection method. For the 40 countries with generalized HIV/AIDS epidemics, the mortality projections used the Spectrum/Estimation and Projection Package (EPP) model, a complex, multistate model designed for short-term projections of policy-relevant quantities for the epidemic. We propose a simpler approach that is more compatible with existing UN projection methods for other countries. Changes in life expectancy are projected probabilistically using a simple time series regression and then converted to age- and sex-specific mortality rates using model life tables designed for countries with HIV/AIDS epidemics. These are then input to the cohort component method, as for other countries. The method performed well in an out-of-sample cross-validation experiment. It gives similar short-run projections to Spectrum/EPP, while being simpler and avoiding multistate modelling.     

中国人口的迁移转变——基于迁移率的考察

经典人口转变理论侧重死亡和生育转变过程的测量、描述和解释,地理学家将迁移转变纳入人口转变框架,以完善人口转变理论。不过与死亡和生育转变研究不同,中国的迁移研究侧重基于对迁移流动人口规模和结构的考察分析,少有采用人口学意义上的迁移率指标的研究。文章利用2010—2015年历次中国综合社会调查的合并数据,通过人口学方法和泊松回归模型,计算和分析了1950—2015年中国人口迁移率趋势及社会经济差异。中国的迁移转变在宏观趋势上与中国的政治经济变迁高度一致。与死亡和生育转变相比,其波折性更强,说明更易受到经济社会政策变化的冲击。同时也观察到逢“0”和逢“5”年份的申报偏好。另外,迁移的社会经济差异明显。男性迁移率高于女性,但是两性差异在不断缩小;乡城迁移和未婚迁移大幅度增长;而越来越多受教育程度较高人群加入迁移,使得受教育程度越高的人群具有越高的迁移率。可以认为基于迁移率的考察揭示了中国迁移转变更具体生动的过程。     

Going Back Home? Changing Demography and Geography of Mexican Return Migration

Return migration has been a constant feature of Mexico?CUS migration patterns, but its characteristics have changed sharply with time. We use the Mexican censuses and counts of 1995, 2000, 2010, and the complete set of individual and household records of the 2005 Population Count to explore the demographic characteristics of returnees in the context of tighter border control and rising levels of forced return migration. Involuntary and therefore unplanned return is likely to mean greater difficulties of incorporation into the community of origin. The study of the effects of the militarization of the US?CMexico border on migration patterns has focused on the US side. We contribute to this literature by focusing on the Mexican side. We consider the intensity and type of previous migration to the US as compared to current return migration, and State of origin and destination. Our data suggest that particularly attractive destinations for returnees are border cities, prosperous communities and growing metropolitan areas. Findings suggest changes in the demographic composition and geographic distribution of returnees. The discordance between the patterns of outmigration and return is a telling indicator of changes in the overall migration relationship between Mexico and the US. The patterns for 2005 are also observed in 2010 even if the absolute number of inter-censal returnees increased threefold over the period. Finally, we argue that focusing on destinations of return instead of areas of emigration will contribute to a more comprehensive understanding on the nature of future return migration to Mexico and its policy implications.     

A Gendered Assessment of Highly Skilled Emigration

Although women form a large and increasing proportion of international migrants, women's mobility has generally been overlooked in the literature. Quantifying and characterizing female migration should lead to a better understanding of the forces that shape international migration. We build an original data set providing gender‐disaggregated indicators of international migration by educational attainment for 195 source countries in 1990 and 2000. We find that women represent an increasing share of the immigration stock in the OECD countries and exhibit higher skilled emigration rates than men.     

Multistate cohort models with proportional transfer rates

We present a new, broadly applicable approach to summarizing the behavior of a cohort as it moves through a variety of statuses (or states). The approach is based on the assumption that all rates of transfer maintain a constant ratio to one another over age. We present closed-form expressions for the size and state composition of the cohort at every age and provide expressions for other useful summary measures. The state trajectories, or life course schematics, depict all the possible size and state configurations that the cohort can exhibit over its life course under the specified pattern of transfer rates. The two living state case and hierarchical multistate models with any number of living states are analyzed in detail. Applying our approach to 1997 U.S. fertility data, we find that observed rates of parity progression are roughly proportional over age. Our proportional transfer rate approach provides trajectories by parity state and facilitates analyses of the implications of changes in parity rate levels and patterns. More women complete childbearing at parity 2 than at any other parity, and parity 2 would be the modal parity in models with total fertility rates (TFRs) of 1.40 to 2.61. Increases in parity progression rates to parities 4 and above have little effect on a cohort's TFR, while changes in childlessness have a substantial impact.     

Low Fertility,Socioeconomic Development,and Gender Equity

While new empirical findings and theoretical frameworks provide insight into the interrelations between socioeconomic development, gender equity, and low fertility, puzzling exceptions and outliers in these findings call for a more all‐encompassing framework to understand the interplay between these processes. We argue that the pace and onset of development are two important factors to be considered when analyzing gender equity and fertility. Within the developed world, “first‐wave developers”—or countries that began socioeconomic development in the nineteenth/early twentieth century—currently have much higher fertility levels than “late developers.” We lay out a novel theoretical approach to explain why this is the case and provide empirical evidence to support our argument. Our approach not only explains historical periods of low fertility but also sheds light on why there exists such large variance in fertility rates among today's developed countries.     

The multistate life table method: An application to contraceptive switching behavior

In many demographic behaviors (e.g., those relating to marriage, contraception, migration, and health), people change among multiple statuses through time, sometimes leaving and then returning to the same status. Data on such behaviors are often collected in surveys as censored event histories. The multistate life table (MSLT) can be used to properly describe, in a single analysis, these complex transitions among multiple states measured in such data, but MSLT is rarely applied in the demographic literature because practical guidance is lacking on how to compute MSLTs with such data. We provide methods for computing MSLT quantities using censored event-history data: namely, transition intensities and probabilities, "state occupancy" probabilities and standard errors, average time spent in specified states, and average number of visits to specified states. Applying these methods to contraceptive use, we find high levels of switching back and forth, particularly between barrier methods and non-use, resulting in high rates of unintended pregnancy.     

The development and use of demographic models

In this review, we first examine two classical demographic models - conventional life tables and stable populations - and a modern generalization of stable population theory; we then discuss mathematical models of conception and birth. These models involve purely mathematical relations in formal demography as opposed to empirical regularities. Next we consider model age schedules of mortality, nuptialitiy, marital fertility, fertility, and migration that are explicitly based on such empirical patterns. We close this empirical section with a discussion of model stable populations, which are based on model life tables. We next examine the use of demographic models in forecasting future mortality, nuptiality, and fertility and in population projection. Following a discussion of microsimulation models, which gives us the opportunity to mention model age schedules of post partum amenorrhoea and of sterility, we close with observations about the purposes and uses of demographic models.     

Multistate Transfer Rate Estimation from Adjacent Populations

In multistate populations, the rates of interstate transfer cannot generally be determined from the size and composition of the populations at the beginning and end of a time interval. With N living states, the population data give only N equations to determine the N ² possible rates. Here, the QERT (quadratic estimation of rates of transfer) approach is advanced that allows the transfer rates to be estimated when the products of selected pairs of rates can be assumed constant. The solution can be written in closed form and, for N living states, involves no more than N?1 quadratic equations. Compared to the leading alternative approaches, QERT provides very similar numerical estimates, while yielding the underlying behavioral rates, having flexible input requirements, accommodating all structural zeros, and reproducing the exact solution when interstate transfers are strictly hierarchical. The QERT approach is applied to construct labor force life tables for U.S. men and women for 2005–2010. The results show that labor force participation differences between men and women have continued to narrow, and that the QERT approach can generate robust worklife estimates. QERT thus provides new opportunities for demographic analysis in the absence of direct data on behavioral rates.     

Dynamic populations with uniform natural increase across states

Multistate populations with changing rates of interstate transfer are an example of compartment models and depict the experience of persons in distinct but intercommunicating states. Such models can be used in analyses of many demographic phenomena, including migration, labor force participation, and health status. This paper extends present knowledge of the relationships prevailing in such dynamic models by developing procedures that yield closed form expressions relating transfer rates to the state-specific population trajectories that they generate. The focus is on a subset of multistate models that do not recognize age and that have restricted variability in rates of transfer and natural increase. Dynamics in the two state, no-growth case, where the two time-varying transfer rates always sum to a constant value, are analyzed in depth. In specified models with any number of intercommunicating states, sine and cosine fluctuations in the transfer rates are shown to yield sine and cosine fluctuations in the numbers of persons in each state.     

Climate,migration, and the local food security context: introducing Terra Populus

Studies investigating the connection between environmental factors and migration are difficult to execute because they require the integration of microdata and spatial information. In this article, we introduce the novel, publically available data extraction system Terra Populus (TerraPop), which was designed to facilitate population–environment studies. We showcase the use of TerraPop by exploring variations in the climate–migration association in Burkina Faso and Senegal based on differences in the local food security context. Food security was approximated using anthropometric indicators of child stunting and wasting derived from Demographic and Health Surveys and linked to the TerraPop extract of climate and migration information. We find that an increase in heat waves was associated with a decrease in international migration from Burkina Faso, while excessive precipitation increased international moves from Senegal. Significant interactions reveal that the adverse effects of heat waves and droughts are strongly amplified in highly food insecure Senegalese departments.     

Indonesia’s social capacity for population health: the educational gap in active life expectancy

In this paper, we lay the initial groundwork for anticipating Indonesia’s future burden of disease by developing a demographic model of population health. We develop this model within the analytic framework of a Markov-based multistate life table model to calculate an important indicator of the burden of disease, the expected years of active life of elderly Indonesians. The magnitude of the gap points to the potential consequences of improvements in the nation’s educational level for the future burden of disease. The results show that having some education increases life expectancy but it also expands the expected years with a major functional problem. Overall educational attainment levels, however, are very low, indicating that Indonesia’s elderly are at the leading edge of improvements in the nation’s social capacity for health. The life tables suggest that at the early stages of development, longer life is accompanied by an expansion of morbidity.     

The third birth in Sweden

This paper considers the formulation, estimation and interpretation of microdynamic models of fertility. Our model explains parity choices, sterility, childlessness, interbirth intervals and initiation of pregnancy within a unified framework. We develop a general methodology for estimating the determinants of transition times to births of different orders. Our procedure incorporates time-varying explanatory variables and unobservables. We present conditions that justify conventional formulae relating hazards to survivor functions when time-varying variables enter hazards. We also consider the validity of widely-used piecemeal estimation strategies that focus on one birth at a time. We consider methods for selecting a best model among a class of non-nested models. Two criteria are set forth and used to evaluate the detminants of third births in Sweden.We find that two models fit Swedish microdata equally well. One model is consistent with neoclassical economic theory. It assigns a central role to the wages of men and women in explaining the timing and spacing of births. The other model is purely demographic and excludes wages. Purely statistical criteria cannot distinguish these models although in other work we show that the economic models are more parsimonious in terms of the number of parameters that must be estimated and are better able to forecast aggregate time series.We demonstrate how to interpret the output of multistate fertility models. Wage effects on third births are decomposed into two components: (a) an in direct effect that determines whether a woman is at risk to have a third birth, and (b) a direct effect on the transition rate to the third birth given that a woman has had two births. We find that female wages play an important role in postponing first births but play only a minor role in explaining childlessness. Female wages substantially affect third births. Male wage effects are weaker. We find that female wage effects weaken for more recent cohorts of women. This evidence is consistent with the introduction of progressively more pronatal Swedish policies.This research was supported by NIH Grant No. HD-19226 to NORC. We have benefited from the comments of Elja Arjas and Ricardo Barros. This paper was presented at an IUSSP Conference in Paris, France, in March 1988, and as an invited lecture at the Fourth ESPE Meetings in Istanbul, Turkey, June, 1990. This paper is one part of a trilogy. Heckman and Walker (1990a) presents a succinct summary of the main economic results. Heckman and Walker (1990b) presents a more complete discussion of the empirical results. This paper presents a more purely demographic discussion.     

Immigration and internal mobility in Canada

We analyse the impact of temporary foreign workers (TFWs) and permanent immigrants on interprovincial mobility in Canada. Empirical results are analysed through the lens of a theoretical model that incorporates a job-matching framework in a migration model à la Harris and Todaro. The effect of the inflow of TFWs in interprovincial mobility is negative, substantial and significant. This is not the case for the inflow of permanent immigrants selected through the Canadian point system. The robustness of these empirical results to issues of endogeneity is assessed through a classical instrumentation approach as well as through a diff-in-diff analysis taking advantage of a pilot project facilitating the admission of TFWs in two Western provinces over the 2007–2010 period. Our paper suggests that, in general, the impact of immigration on labour market conditions depends critically on the way immigration policy is set.