Efficient heterogeneous sampling for stochastic simulation with an illustration in health care applications

In modeling disease transmission, contacts are assumed to have different infection rates. A proper simulation must model the heterogeneity in the transmission rates. In this article, we present a computationally efficient algorithm that can be applied to a population with heterogeneous transmission rates. We conducted a simulation study to show that the algorithm is more efficient than other algorithms for sampling the disease transmission in a subset of the heterogeneous population. We use a valid stochastic model of pandemic influenza to illustrate the algorithm and to estimate the overall infection attack rates of influenza A (H1N1) in a Canadian city.     

Determinants of contraceptive switching behavior in rural Sri Lanka

This study examines the influence of a selected set of determinants of contraceptive method switching in rural Sri Lanka. Of interest is the question of how change in contraceptive practice at the individual level can account for patterns observed at the aggregate level. Based on calendar data on contraceptive use over a 3-year period, collected for more than 3,000 married women in a 1986 survey, the multivariate analysis shows that women who attain all or a significant proportion of their desired fertility tend to switch to more effective methods. Women who experience method failure tend to switch methods, usually to a type that is more effective. The woman's background determinants of age and education have small but significant effects on method switching, whereas the effect of household economic well-being is not significant. There is strong indication that rural couples are practicing contraception in a nonrandom fashion, switching methods in accordance with changes in their fertility motivations and contraceptive experience.     

Multidimensional poverty indices

This paper explores the axiomatic foundation of multidimensional poverty indices. Departing from the income approach which measures poverty by aggregating shortfalls of incomes from a pre-determined poverty-line income, a multidimensional index is a numerical representation of shortfalls of basic needs from some pre-specified minimum levels. The class of subgroup consistent poverty indices introduced by Foster and Shorrocks (1991) is generalized to the multidimensional context. New concepts necessary for the design of distribution-sensitive multidimensional poverty measures are introduced. Specific classes of subgroup consistent multidimensional poverty measures are derived based on sets of reasonable axioms. This paper also highlights the fact that domain restrictions may have a critical role in the design of multidimensional indices. Received: 1 March 1999/Accepted: 1 August 2000     

澳门旅游博彩形象的实证研究

澳门博彩业回归后迅速发展,随著"澳门历史城区"被列入"世界文化遗产",该行业更出现前所未有的繁荣景象。然而,除了"赌城"的形象外,澳门的旅游博彩形象还有甚么元素呢?本文结合了"结构法"与"非结构法",针对澳门旅游博彩形象进行问卷调查,来了解它的内涵及意义,并尝试提出一些适合澳门旅游博彩形象发展的建议,以利澳门这个"龙头"产业的可持续发展。     

Multiparameter estimation of discrete exponential distributions

Let X₁, …, X_p be independent random variables, all having the same distribution up to a possibly varying unspecified parameter, where each of the p distributions belongs to the family of one parameter discrete exponential distributions. The problem is to estimate the unknown parameters simultaneously. Hudson (1978) shows that the minimum variance unbiased estimator (MVUE) of the parameters is inadmissible under squared error loss, and estimators better than the MVUE are proposed. Essentially, these estimators shrink the MVUE towards the origin. In this paper, we indicate that estimators shifting the MVUE towards a point different from the origin or a point determined by the observations can be obtained.     

Declining world fertility: trends,causes, implications

This Bulletin examines the evidence that the world's fertility has declined in recent years, the factors that appear to have accounted for the decline, and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world, the authors derive estimates which indicate that the world's total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975, thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors' projections, which are compared to similar projections from the World Bank, the United Nations, and the U.S. Bureau of the Census, indicate that, by the year 2000, less than 1/5 of the world's population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."     

Conjuncture and cultural reproduction in the process of embedding: social work practice in the context of government purchase of services in China

This paper focuses on the Chinese government’s policy of purchasing social services and discusses how relevant organisations provide social work and develop it within local socio-political and cultural contexts. An ethnographic research method was adopted for the study by the first author while participating in social work development in Q City. We argue that the policy of purchasing social services succeeded in achieving “embedded development” but also created a “conjuncture structure” in cultural reproduction. However, due toprofessional social workers in China have, in practice, passively responded to the conjuncture there has been a failure to reproduce professional values of social work in the Chinese cultural context. Therefore, further development of social work in China needs to strengthen cultural reflection in practical actions, focus on the exploration of cultural connections between social work practice and local communities, and enhance the cultural capacity of social workers in the local cultural context.     

Effective design of a global leadership programme

The purpose of this paper is to report level 3 evaluation findings from a leadership development programme. This paper comprises a case study, quantitative data analysis, and results from critical incident semi-structured interviews. A unique research model was developed from a literature review. There are many problems associated with the design and delivery of leadership development programmes. Senior executive-taught workshops, 360° feedback, and action learning were deliberately employed to increase the adoption and application of specific behaviours after the programme. The results substantiate previous findings on the impact of these elements by demonstrating concrete behavioural changes rather than perceived enhancement in leadership capabilities as often cited in other studies. The model should be further tested, applied and refined as necessary.

Organizations wishing to develop leaders could be guided by the model and findings of this research. A novel and innovative design model was developed from a literature review, tested against a leadership programme in a large well-known multi-national organization, and later refined based on the empirical results. It will be of value to HRD managers and researchers.