Gender-specific differences in labor market adjustment patterns: Evidence from the United States

Do men and women behave differently while adjusting labor supply over the business cycle? Using data from the United States, we show that women are significantly more likely to adjust along the intensive margin (number of hours), while men adjust more along the extensive margin (employment). Older, single, and divorced/widowed adjust predominantly along the extensive margin.     

Assessing the validity of a single-item HIV risk stage-of-change measure

This study examined the validity of a single-item measure of HIV risk stage of change that HIV prevention contractors were required to collect by the California State Office of AIDS. The single-item measure was compared to the more conventional University of Rhode Island Change Assessment (URICA). Participants were members of Los Angeles County-defined behavioral risk groups recruited from a mobile HIV testing program (N = 123). The study found low correspondence between participants' stage of change on the single-item and the URICA, suggesting that they do not assess the same construct, and that the single item may not provide a valid measure. The current data suggests that the single-item measure should be revised or abandoned in favor of more conventional stage-of-change measures.     

数学之王丘成桐

1979年,当时在普林斯顿高等研究所任职的数学家丘成桐访问中国,并提请当时的政府官员允许他去探望一下他的出生地汕头--坐落在广东省的一个山区城镇.     

A components method for measuring the impact of a family planning program on birth rates

One of the major goals of family planning programs worldwide has been to reduce the level of fertility in hopes of slowing the rate of natural increase and promoting social and economic development. Such programs have now been in existence for sufficient lengths of time to have had an impact on fertility levels. In general countries with organized family planning programs, marked declines in fertility levels have been observed. The extent to which such declines may be credited to organized programs has not been rigorously measured because an appropriate research methodology has been lacking. This paper describes one method of directly linking declines in fertility levels to the contraceptive protection experienced by a population. The contribution of organized family planning programs is estimated by decomposing the amount of total contraceptive protection into within-program and outside-program sources.     

Is population growth a deterrent to development in the South Pacific?

Some have argued that population growth deters development, while others claim that population growth either aids development or has no significant effect on development. In a sample of South Pacific nations, population growth and size were found to be unrelated to economic development, defined as GDP per capita. However, when indices of quality of life or social development such as mortality, health services and education were used, population growth and size were found to be negatively related to these indices. If these “quality of life” indices are valued by nations, an argument may exist for policy support for family planning.     

Life table techniques for multiple-cause mortality

A lethal defect-wear model of mortality is presented which rationalizes the assumption of independent risks when death may be due to more than a single condition, Under this model, it is shown how competing risk theory and standard categorical data methods may be merged in a unified approach to the analysis of multiple-cause mortality data. The methodology is used to analyze linkages among diseases in the mortality data and evaluate the implication of the elimination of patterns of morbid states for multiple-cause mortality data from deaths occurring in 1969 in North Carolina.     

Remittances and the income distribution in Tonga

Receipt of remittances from migrants decreased the inequality of income in Tonga. Policies that attempt to affect migration or remittance flows, such as policies to improve the administration and collection of taxes, should take into account any undesirable effects on the distribution of income.     

Antecedents to contraceptive innovation: Evidence from rural Northern Thailand

A number of different causal mechanisms have been proposed to explain the onset of fertility declines in populations with previously uncontrolled fertility, but they have never been adequately tested. The present study identifies and tests five antecedents to family limitation practices in a sample of 755 currently married couples resident in rural Northern Thailand. The loglinear multiple regression models estimated indicate that couples in more developed districts, more modern couples, couples in which wives have more equal roles, couples believing that intergenerational wealth transfers favor children rather than their parents, and more wealthy couples, were all significantly more likely to be early adopters of contraception. Local development levels appeared to have the greatest net effects on the timing of adoption of fertility control. In addition, couples in areas where contraceptive services were more readily available were also significantly more likely to be contraceptive innovators, net of these five variables.     

Bewertung intertemporaler Abh?ngigkeiten zwischen IT-Projekten

Companies often decide in favour of IT investments (especially IT infrastructure investments) only because these investments build the foundation for more lucrative follow-up investments. Those intertemporal interdependencies among IT projects have to be considered within the scope of a value-based IT portfolio management. Therefore, current literature suggests the use of real options analysis??and therefore the application of option pricing models such as the binomial model or the Black-Scholes model. Both models require a complete market. However, because IT projects are characterized by project specific risks, which cannot be duplicated on a capital market, the forthright application of these models is problematic. This issue has been addressed within the scope of the discrete binomial model so far. In this paper we transfer these findings to the Black-Scholes model. Furthermore, we apply this approach to a real case and illustrate how a correct consideration of project specific risks using the Black-Scholes model can affect investment decisions.