Narrow Results

We have adapted the Penna ageing model to simulate the profound changes in the age structures of populations caused by the better life style, medical care and decrease in birth rate. In Poland, after the political transformations in the last decade of the twentieth century, the increase in the expected lifespan has been accompanied by very deep decrease in birthrate, much below the minimum necessary for keeping the constant size of the population. Our microscopic model describes the changes in the age structure which have already happened and predicts the future, assuming that our attitudes in respect to life style and social relations will not change.

In this article, we propose a network spreading model for HIV epidemics, wherein each individual is represented by a node of the transmission network and the edges are the connections between individuals along which the infection may spread. The sexual activity of each individual, measured by its degree, is not homogeneous but obeys a power-law distribution. Due to the heterogeneity of activity, the infection can persistently exist at a very low prevalence, which has been observed in the real data but cannot be illuminated by previous models with homogeneous mixing hypothesis. The model displays a clear picture of hierarchical spread: In the early stage the infection is adhered to these high-risk persons, and then, diffuses toward low-risk population. Furthermore, we find that to reduce the risky behaviors is much more effective in the fight against HIV/AIDS rather than the antiretroviral drug therapies. The prediction results show that the development of epidemics can be roughly categorized into three patterns for different countries, and the pattern of a given country is mainly determined by the average sex-activity and transmission probability per sexual partner. In most cases, the effect of HIV epidemics on demographic structure is very small. However, for some extremely countries, like Botswana, the number of sex-active people can be depressed to nearly a half by AIDS.

The trajectory of Singapore's population size and composition can be mapped out with its progression through the various phases of demographic transition from high birth and death rates in the post-war years to very low birth and death rates today, all within the context of rapid economic and social development that has taken place in the past 50 years. Population planning has been integral in Singapore's national development strategy, balancing the economy's needs for more and better qualified workers with social considerations such as the dependency burden and the integration of large numbers of foreigners in a global city-state. This paper considers Singapore's population and manpower planning policies, with an account of the country's passage through the various stages of its demographic transition, and how its working age population composition has evolved. Population and labor force policies are examined with specific consideration of the social, economic and political implications resulting from those policy choices. A final section considers the challenges for the future stemming from these demographic trends.

Global debt will keep growth subdued over the next decade. Falling work force will move labor intensive manufacturing out of China and into South Asia. Investment, not consumption, will be the main driver of growth, which primarily will take place in Asia and probably also Africa. New institutional frameworks such as AIIB emerge, but they will operate inside the existing global order. Falling albeit still tangible Chinese saving combined with fading interest for US treasury bonds will pose an awkward dilemma for US monetary policy. Under such circumstances current savings–investment balances will continue to rule the global economy.

The devastating figures that recently emerged from a demographic study of the impact of HIV/AIDS in some African countries mark the return to the conditions of the XIXth century, when high birth rates were neutralized by equally high death rates. In the State of São Paulo, Brazil, AIDS is the second cause of death among men aged twenty to forty nine years and the first cause of death of women in the same age class. In this work we propose a mathematical treatment to evaluate the impact of AIDS mortality on the age structure of an affected population, namely, that of the state of São Paulo, Brazil. We propose four indicators for the estimation of the impact of AIDS mortality. The first is the age-dependent differences in ten years survival probabilities attributable to AIDS. The second is the difference in the average age of survivors after 10 years of AIDS. The next is the conventional life expectancy at birth for children born in 1996 and with AIDS prevalence assumed at its maximum value and remaining in steady-state afterwards. Finally, we calculate the differences in the life expectancy of individuals considering the effect of AIDS for only ten years. We found that, in the period between 1987 and 1996 the effects were small but very interesting. However, projecting to the future the conditions of 1996, we calculate that the population of the state of São Paulo would lose 3 years in the average life expectancy at birth.

This paper uses loan-level data from Thailand's National Credit Bureau to study household debt over the life cycle of borrowers. We decompose two aggregate and commonly used measures of debt—debt per capita and delinquency rate—into components that unveil the extensive and intensive margins of household indebtedness. We find a striking inverted-U life-cycle pattern of indebtedness as predicted by economic theories. However, peaks are reached at different ages for different loan products and different lenders. We also find that debt has expanded over time for all age groups. Younger cohorts seem to originate debt earlier in their lives than older generations. Meanwhile, older borrowers remain indebted well past their retirement age. Finally, we find a downward pattern of delinquency over the life cycle. Our findings have important policy implications on financial access and distress of households as well as on economic development and financial stability of the economy.

This paper re-examines the impact of demographic factors on the current account balance. To this end, we develop an analytical framework that is more general than the one commonly used in the literature in three aspects. First, it accounts for the facts that the world current account balance must be equal to zero. Second, a bigger economy will have greater impacts on others, but be influenced less by them. Third, a more open economy will have greater impacts on others and at the same time be more readily influenced by them. We then confront two alternative empirical specifications based on both the new and the conventional framework with a panel of data. In contrast to the findings based on the conventional framework, our results with the new framework indicate that population ageing does not appear to have discernible impacts on the current account balance.