Patient progress modelling and results in Wilm's Tumour

The report describes the development of a mathematical model of the progress of patients with Wilm's Tumour using the methodology developed by Jackson & Aspden [1, 2]. The model incorporates two prognostic factors which are shown to influence patient progress. These are the stage of the tumour and the age of the patient at presentation. The model proved adequate to represent an initial set of patient data, and comparison runs were performed with data from a later time period. These runs highlighted changes in patient progress between the two groups and illustrated the usefulness of the model in this type of analysis. The analysis also underlined the poor prognosis of patients over 5 years old who relapsed.     

Student-Athletes and Gambling: An Analysis of Attitudes Towards Risk-Taking

Gambling scandals at Arizona State University, Boston College, and Northwestern University have made gambling prevention a point of emphasis in the NCAA and throughout colleges and universities across the nation. Despite this emphasis, there is minimal research at any level regarding gambling and student-athletes. This research examines attitudinal differences towards risk-taking among student-athletes who gamble on college sports and those who indicate no such gambling activity. Our findings indicate that student-athletes who gambled were more likely to have attitudes supportive of risk taking behavior than their student-athlete peers who did not gamble.     

The Lost Value of Groundwater and its Influence on Environmental Decision Making

A critical aspect in establishing environmental policies lies in the proper assessment of the value of the resource being affected. Standard risk assessment analyses calculate the cost of pollution as consisting, solely, of the cost to remediate a site. This traditional definition is extended here to include the lost value of groundwater. These concepts and their impact on decision-making analyses are illustrated through the case of municipal waste landfills. Based on data from existing polluting sites, a simple cost-benefit probabilistic analysis is conducted first, which equates, as is the practice, the cost of pollution to that of remediation. This leads rationally to selection of the lowest-protection technology. Using plausible arguments the reduction in value of groundwater from potable high-quality water to irrigation water, which is what is returned after remediation, is argued. The arguments consist of: (a) the ratio of the subsidized prices of drinking to irrigation water reflects the relative value of the use of water; (b) the amount paid for remediation, in each case, represents, at a minimum, the value of the water recovered; and (c) the lost value of groundwater equals the value of drinking water minus the value of irrigation water. Incorporation of this lost value of groundwater is sufficient to drastically alter the conclusions of the decision-making analysis and make the highest level technology the most rational and profitable alternative. The broader point of this article lies in that proper accounting of environmental costs is necessary in order to alter environmental policies and practices.     

Fiscal rules in a volatile world: A welfare-based approach

It is widely agreed that a fiscal rule should boost discipline and credibility. A rule should also reduce macroeconomic volatility and be easily understood. Toward such ends, a government may run structural surpluses. In so doing, the government accumulates a precautionary cushion of assets on behalf of agents who do not enjoy access to capital markets. As an additional criterion, that level of assets should be bounded. We provide an example of a structural surplus rule that satisfies all such criteria. In our general equilibrium simulations, we show that such a rule benefits credit-constrained consumers but may hurt others.     

From bedside to bench: research agenda for frailty

The American Geriatrics Society sponsored a working conference in January 2004, funded by the National Institute on Aging, to establish the state of the art in frailty research and to set a research agenda for the future. The invited participants included senior basic biologists, epidemiologists, geneticists, and clinical investigators who study aging-related issues. This article summarizes the central theoretical observations on frailty and research needs and opportunities presented and discussed at this conference, and lays out an agenda for future research on frailty.     

Multi‐Echelon Inventory Management under Short‐Term Take‐or‐Pay Contracts

We extend the Clark–Scarf serial multi‐echelon inventory model to include procuring production inputs under short‐term take‐or‐pay contracts at one or more stages. In each period, each such stage has the option to order/process at two different cost rates; the cheaper rate applies to units up to the contract quantity selected in the previous period. We prove that in each period and at each such stage, there are three base‐stock levels that characterize an optimal policy, two for the inventory policy and one for the contract quantity selection policy. The optimal cost function is additively separable in its state variables, leading to conquering the curse of dimensionality and the opportunity to manage the supply chain using independently acting managers. We develop conditions under which myopic policies are optimal and illustrate the results using numerical examples. We establish and use a generic one‐period result, which generalizes an important such result in the literature. Extensions to cover variants of take‐or‐pay contracts are included. Limitations are discussed.     

‘We can play tag with a stick’. Children's knowledge,experiences, feelings and creative thinking during the COVID-19 pandemic

Using a relational approach, we draw on repeated interviews with a group of 30 diverse children from Ontario to share and reflect on their knowledge, experiences and feelings early in the COVID-19 pandemic. Prioritising relational interdependence and relational agency, this paper illustrates our participants' embedded engagements with the pandemic and their contribution to the co-production of knowledge. We emphasise their thoughtful responses to the pandemic; their creative, self-reflexive strategies for managing a difficult time; and their advice to others. We thus prioritise children's viewpoints and emphasise their relational interconnections with others during a time that was marked by social isolation.     

DETERMINING THE MOST PROFITABLE RETAIL BRAND MIX FROM EMPIRICAL MEASURES OF BRAND PREFERENCE

This paper refers to the brand-preference parameters of a previously accepted empirical model, and axiomatically generates several basic propositions and their proofs, which define the retail store's most profitable short-run blend of product brands.