Constructions of given-depth and optimal multirate rearrangeably nonblocking distributors

Rearrangeable multirate multicast switching networks are customarily called rearrangeable multirate distributors. It has been known for a long time that rearrangeable multirate distributors with cross-point complexity O(nlog?² n) can be constructed, where n is the number of inputs (and outputs) of the switching network. The problem of constructing optimal distributors remains open thus far. This paper gives a general construction of rearrangeable multirate distributors with given depths. One byproduct is a rearrangeable multirate distributor with crosspoint complexity O(nlog?n). We also show that this cross-point complexity is optimal, settling the aforementioned open problem. One of the key ingredients of our new construction is the notion of multirate concentrators. The second ingredient is a multirate version of the Pippenger network. We show how to construct given-depth multirate concentrators and given-depth multirate Pippenger networks with small sizes. When the depth is chosen to optimize the size, we obtain the optimal O(nlog?n) cross-point complexity.     

Implications of economic reform and spatial mobility for fertility in Vietnam

Vietnam has registered a dramatic decline in fertility during the last decades. While the causes of such a sustained decline are still not well documented, many observers believe that government policies adopted in the 1980s have contributed to lower fertility. This article focuses on the implications of the Doi Moi program of market reforms on fertility, taking into account the influences of migration and population policy. The analysis is based on a sequential logit model of birth histories of ever married women interviewed in Vietnam in 1997. The results show a substantial decline in fertility since the Doi Moi program was introduced. The disruptive effects of migration are less pronounced, although migrants generally exhibit lower childbearingrates, and a somewhat different pattern of parity progression. We argue that the economic reforms of 1986, and the two-child policy initiated two years later, have reinforcedVietnamese women's desire for smaller families.     

Culturally appropriate pedagogy: the case of group learning in a Confucian Heritage Culture context

Cultural heritage preservation has become a much‐debated topic in recent decades. This paper contributes to the call for educational approaches that take a society's cultural diversity into account. It also attempts to draw attention to non‐Western societies, where educational theories and practices from elsewhere (the West) have been imported and applied without proper consideration for the host culture's heritage. To illustrate the intricacy of developing such a culturally appropriate pedagogy, a case study of using group learning strategies in a Confucian Heritage Cultural context is introduced, which closely examines both educational and cultural issues. The results of this examination reveal a complex web of cultural conflicts and mismatches that are likely to happen when a Western educational methodology is applied in another context without rigorous adaptation to improve compatibility with the host culture.     

Engaging girls with disabilities in Vietnam: making their voices count

This article addresses a theoretical and methodological intervention in support of inclusion for girls with disabilities in Vietnam. Drawing on an internationally collaborative project, Monitoring Educational Rights for Girls with Disabilities in Vietnamese schools, we critically engage the politics of inclusion and exclusion of girls with disabilities in education. Using a critical methodological framework that foregrounds the lived experiences of 21 girls with disabilities in Vietnam, we ask how we might strengthen participatory knowledge production through the work of monitoring rights in order to inform practices and policies related to disability and education. Through a preliminary analysis of the visual data emerging from our participatory visual methodologies, we demonstrate how these methods can contribute to constructing more inclusive practices and policies for girls with disabilities in both the Vietnamese and the global contexts.     

Post-high school choices: New evidence from a multinomial logit model

A multinomial logit model is estimated to investigate the destination of students one-year after graduating from high school. The appropriate specification of the choice set available to high school leavers is as follows: private four-year college, public four-year college, private two-year college, public two-year college, employed and unemployed. We test for several possible combinations of these choices and find that these pooled models are all rejected in favour of the full model. The transition from high school to college and to work is more complex than previous studies have recognised. Received: 12 July 2002/Accepted: 2 November 2002 All correspondence to Jim Taylor. The authors are grateful to Steve Bradley and an anonymous referee for valuable comments on a previous draft of this paper. We alone are responsible for the errors and omissions. Anh Nguyen is grateful to the ESRC for providing financial support. Responsible editor: Daniel S. Hamermesh.     

Empathy and drug use behaviors among African-American adolescents

The current study proposed that empathy may indirectly play a protective role for adolescents in drug use behaviors and that this relationship will be mediated by self-regulatory strategies found in drug refusal efficacy. We predict that empathy will be linked to prosocial behavior and aggression, though we do not believe that they will mediate the relationship between empathy and drug use. The sample included 498 African-American adolescents in the 6th, 7th, and 8th grade. The results of structural equation modeling provided support for our hypotheses. Empathy was significantly and positively associated with drug refusal efficacy and prosocial behavior. Empathy was negatively associated with aggression. Drug refusal efficacy was negatively related to past 30-day drug use, providing evidence for the fully mediating role of drug refusal self-efficacy on empathy and past 30-day drug use. Consistent with our predictions, aggression and prosocial behavior were not significantly associated with past 30-day drug use. These findings may be useful in the context of programming efforts for drug prevention.     

Impact of Public and Private Cash Transfers on Poverty and Inequality: Evidence from Vietnam

This article investigates the extent to which public and private transfers affected poverty and inequality in Vietnam in the mid‐2000s. It finds that the impact of public transfers on poverty was negligible, due to the low coverage of the poor and the relatively small amounts transferred. Moreover, the effect of the receipt of transfers on expenditures was small: recipients decreased the labour supply and only a limited amount of the extra income went to current consumption. Domestic private transfers were somewhat more successful in reducing poverty. With most public and private transfers going to non‐poor households, inequality was only marginally affected.     

Valuing Equal Protection in Aviation Security Screening

The growing number of anti‐terrorism policies has elevated public concerns about discrimination. Within the context of airport security screening, the current study examines how American travelers value the principle of equal protection by quantifying the “equity premium” that they are willing to sacrifice to avoid screening procedures that result in differential treatments. In addition, we applied the notion of procedural justice to explore the effect of alternative selective screening procedures on the value of equal protection. Two‐hundred and twenty‐two respondents were randomly assigned to one of three selective screening procedures: (1) randomly, (2) using behavioral indicators, or (3) based on demographic characteristics. They were asked to choose between airlines using either an equal or a discriminatory screening procedure. While the former requires all passengers to be screened in the same manner, the latter mandates all passengers undergo a quick primary screening and, in addition, some passengers are selected for a secondary screening based on a predetermined selection criterion. Equity premiums were quantified in terms of monetary cost, wait time, convenience, and safety compromise. Results show that equity premiums varied greatly across respondents, with many indicating little willingness to sacrifice to avoid inequitable screening, and a smaller minority willing to sacrifice anything to avoid the discriminatory screening. The selective screening manipulation was effective in that equity premiums were greater under selection by demographic characteristics compared to the other two procedures.