A framework for valuing derivative securities

This paper develops a general framework for valuing a wide range of derivative securities. Rather than focusing on the stochastic process of the underlying security and developing an instantaneously-riskless hedge portfolio, we focus on the terminal distribution of the underlying security. This enables the derivative security to be valued as the weighted sum of a number of component pieces. The component pieces are simply the different payoffs that the security generates in different states of the world, and they are weighted by the probability of the particular state of the world occurring. A full set of derivations is provided. To illustrate its use, the valuation framework is applied to plain-vanilla call and put options, as well as a range of derivatives including caps, floors, collars, supershares, and digital options.

Beyond sex and cooking: Health education for individuals with intellectual disability

Issues of health education programming for people with intellectual disability are discussed. As environments in which such individuals live become more inclusive, and they are encouraged to make their own choices, the issue of whether current health education is sufficient to enable them to make healthy life choices is considered. More attention should be focused on programs in schools and the community to fulfill this need. Three aspects of health education programming are considered: physical activity, general health knowledge, and social supports for health. Continuity of information is viewed as important in policy development as well as in interprofessional coordination and cooperation to assure that these individuals are not further handicapped by poor health.

An empirical framework for studying desistance as a process

Recent reviews of the desistance literature have advocated studying desistance as a process, yet current empirical methods continue to measure desistance as a discrete state. In this paper, we propose a framework for empirical research that recognizes desistance as a developmental process. This approach focuses on changes in the offending rare rather than on offending itself We describe a statistical model to implement this approach and provide an empirical example. We conclude with several suggestions for future research endeavors that arise from our conceptualization of desistance.

Sterilization of girls and women with intellectual disabilities - Past and present justifications

This article describes findings from empirical research examining sterilization applications for miners made to the Family Court of Australia between 1992 and 1999. Original materials and written reports from experts,family members, and judicial officers are used to highlight the dominant discourse and themes. These are compared with historical characterizations of young women with disabilities used during the notorious eugenics period in the first half of the 20th century. The new ways of justifying sterilization use the sanitized language of best interests, silencing constructionist approaches to disability and gender issues. The new ways are reminiscent of the old ways of discrimination, prejudice, and violation.

Intellectual origins of welfare dependency

'Welfare dependency' has become a key term in policy debate in the United States and, more recently, Australia. In this article I explore the intellectual origins of the term, looking specifically at the writings of George Gilder and Charles Murray, two commentators whose (often polemically presented) ideas were influential within the Reagan Administration and have been at the forefront of a conservative renewal in welfare debate generally. Although others have subsequently refined some of their arguments and proposals, the authors' central claim that welfare causes dependency and thus unemployment and poverty - and that welfare reform therefore needs to focus on changing the behaviour of welfare recipients rather than providing employment opportunities - has had a lasting political impact, in Australia as much as in the US.

Habitat complexity, spatial interference, and "minimum risk distribution": a framework for population stability

In the past century, the debate over whether or not density-dependent factors regulate populations has generally focused on changes in mean population density, ignoring the spatial variance around the mean as unimportant noise. In an attempt to provide a different framework for understanding population dynamics based on individual fitness, this paper discusses the crucial role of spatial variability itself on the stability of insect populations. The advantages of this method are the following: (1) it is founded on evolutionary principles rather than post hoc assumptions; (2) it erects hypotheses that can be tested; and (3) it links disparate ecological schools, including spatial dynamics, behavioral ecology, preference-performance, and plant apparency into an overall framework. At the core of this framework, habitat complexity governs insect spatial variance. which in turn determines population stability. First, the minimum risk distribution (MRD) is defined as the spatial distribution of individuals that results in the minimum number of premature deaths in a population given the distribution of mortality risk in the habitat (and, therefore, leading to maximized population growth). The greater the divergence of actual spatial patterns of individuals from the MRD, the greater the reduction of population growth and size from high, unstable levels. Then, based on extensive data from 29 populations of the processionary caterpillar, Ochrogaster lunifer, four steps are used to test the effect of habitat interference on population growth rates. (1) The costs (increasing the risk of scramble competition) and benefits (decreasing the risk of inverse density-dependent predation) of egg and larval aggregation are quantified. (2) These costs and benefits, along with the distribution of resources, are used to construct the MRD for each habitat. (3) The MRD is used as a benchmark against which the actual spatial pattern of individuals is compared. The degree of divergence of the actual spatial pattern from the MRD is quantified for each of the 29 habitats. (4) Finally, indices of habitat complexity are used to provide highly accurate predictions of spatial divergence from the MRD, showing that habitat interference reduces population growth rates from high, unstable levels. The reason for the divergence appears to be that high levels of background vegetation (vegetation other than host plants) interfere with female host-searching behavior. This leads to a spatial distribution of egg batches with high mortality risk, and therefore lower population growth. Knowledge of the MRD in other species should be a highly effective means of predicting trends in population dynamics. Species with high divergence between their actual spatial distribution and their MRD may display relatively stable dynamics at low population levels. In contrast, species with low divergence should experience high levels of intragenerational population growth leading to frequent habitat-wide outbreaks and unstable dynamics in the long term. Six hypotheses, erected under the framework of spatial interference, are discussed, and future tests are suggested.

Healthy ageing - Adults with intellectual disabilities: Physical health issues

This report has been prepared by the Ageing Special Interest Research Group of the International Association for the Scientific Study of Intellectual Disabilities (IASSID) in collaboration with the Department of Mental Health and Substance Dependence and the Programme on Ageing and Health, World Health Organization (WHO), Geneva, Switzerland, and all rights are reserved by the above mentioned organization. The document may, however, be freely reviewed, abstracted, reproduced or translated in part, but not for sale or use in conjunction with commercial purposes. It may also be reproduced in full by non-commercial entities for information or for educational purposes with prior permission from WHO/IASSID. The document is likely to be available in other languages also.

Audit and comprehensive health assessment programme in the primary healthcare of adults with intellectual disability: a pilot study

International research has demonstrated significant shortcomings in the health of adults with intellectual disability (ID). Because general practitioners (GPs) are the main providers of primary healthcare for this population, strategies to improve general practice care are an important aspect of rectifying these shortcomings. The present pilot study aimed to determine the effect of various interventions on health maintenance activities and to assess their acceptability to GPs, with a view to informing larger scale studies. The GPs were recruited through an earlier questionnaire-based postal survey. The GPs identified all their adult patients with ID, then obtained consent for participation from three patients randomly selected by the investigators. The GPs completed two self-evaluation forms and case note audits 12 months apart, read a synopsis of the relevant literature provided by the researchers, and completed a comprehensive health assessment (CHA) of their three patients. Forty-five GPs agreed to participate in the CHA programme (CHAP), and 15 completed the project. Thirty-eight patients completed the project. The number of patient-GP dyads who completed the project was too small to demonstrate statistically significant changes in health issues over time. The GPs found that the synopsis of the literature was the best intervention for increasing knowledge and was also the most practical to use in general practice. The CHAP was the intervention that prompted the most action from the GP which would not have been undertaken otherwise. The CHAP appeared to provide a superior review process compared to the other interventions used in the present study. The numbers of health maintenance activities found to be overdue and the number of health issues detected as a result of the process were considerable. The CHAP served as a communication tool and an educative instrument, providing a basis for future studies and strategies to improve the general practice care of adults with ID.

Saving, productivity and national income: a discrete-time geometric framework

This paper proposes an alternative geometric framework for analysing the inter-relationship between domestic saving, productivity and income determination in discrete time. The framework provides a means of understanding how low saving economies like the United States sustained high growth rates in the 1990s whereas high saving Japan did not. It also illustrates how the causality between saving and economic activity runs both ways and that discrete changes in national output and income depend on both current and previous accumulation behaviour. The open economy analogue reveals how international capital movements can create external account imbalances that enhance income growth for both borrower and lender economies. (C) 2002 Elsevier Science B.V. All rights reserved.