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101.
Abstract

The sustained reduction in mortality rates and its systematic underestimation has been attracting the significant interest of researchers in recent times because of its potential impact on population size and structure, social security systems, and (from an actuarial perspective) the life insurance and pensions industry worldwide. Despite the number of papers published in recent years, a comprehensive review has not yet been developed.

This paper attempts to be the starting point for that review, highlighting the importance of recently published research—most of the references cited span the last 10 years—and covering the main methodologies that have been applied to the projection of mortality rates in the United Kingdom and the United States. A comparative review of techniques used in official population projections, actuarial applications, and the most influential scientific approaches is provided. In the course of the review an attempt is made to identify common themes and similarities in methods and results.

In both official projections and actuarial applications there is some evidence of systematic overestimation of mortality rates. Models developed by academic researchers seem to reveal a trade-off between the plausibility of the projected age pattern and the ease of measuring the uncertainty involved. The Lee-Carter model is one approach that appears to solve this apparent dilemma.

There is a broad consensus across the resulting projections: (1) an approximately log-linear relationship between mortality rates and time, (2) decreasing improvements according to age, and (3) an increasing trend in the relative rate of mortality change over age. In addition, evidence suggests that excessive reliance on expert opinion—present to some extent in all methods—has led to systematic underestimation of mortality improvements.  相似文献   
102.
Maya Van Leemput 《Futures》2010,42(4):370-379
This paper presents results from the Iris Futures research project. The research was aimed at exploring the potential role of foresight in the development of the Brussels Capital Region and the identification of tools, capabilities and conditions for an improved application of foresight in Brussels. An overview was created of the characteristics of 60 future oriented activities and 120 organisations involved in such activities At the outset questions on organisational or institutional fragmentation and collaboration were not intended to be in the foreground of the research but over the course of the research this issue was observed to have a significant adverse impact on foresight capacity in Brussels. The case of the Brussels Capital Region demonstrates that institutional and organisational fragmentation need to be overcome for a futures oriented practice to have opportunity. De-fragmentation, bottom-up and institutionally, is both a condition for and an effect of the futures oriented practice underlying the foresight capacity of organisations.  相似文献   
103.
This article explores the way in which a major Australian radiology organization implemented a complex accounting information system and how workers in the 72 radiology practices that had to use it resisted the change. The study reports on the issues that led to the circumvention of the system by individuals and, after only three years, complete withdrawal of the accounting information system by the parent organization. This article has implications for firms in the health care and other sectors considering implementing new accounting information systems. Organizations need to incorporate change management techniques and provide open communication to all stakeholders to minimize disruption and potential problems.  相似文献   
104.
This article offers some reflections on opportunities and challenges for management accounting research in the wake of the recent financial crisis, and especially the regulatory reforms and augmented disclosures the crisis has spawned. While challenging for the organizations facing them, I argue that especially the enhanced disclosures are likely to turn management accounting ‘inside out’ to a greater extent than has been the case before, which could be a boon for researchers studying hitherto mostly internal management accounting practices. As an undercurrent to the opportunities for research, however, I emphasize the importance of considering organizational design, comprised of both structure and culture, in understanding the inevitably intertwined effects of distorted incentives and information failings, among other problems that seem to all have contributed in some way to the crisis. In respect of the opportunities for management accounting research, I mainly discuss a continuing need to study incentives; a motivation to study risk management; an opportunity to reinvigorate budgeting research; and an invitation to study financial companies and the challenges of disclosures.  相似文献   
105.
When handling missing data, a researcher should be aware of the mechanism underlying the missingness. In the presence of non-randomly missing data, a model of the missing data mechanism should be included in the analyses to prevent the analyses based on the data from becoming biased. Modeling the missing data mechanism, however, is a difficult task. One way in which knowledge about the missing data mechanism may be obtained is by collecting additional data from non-respondents. In this paper the method of re-approaching respondents who did not answer all questions of a questionnaire is described. New answers were obtained from a sample of these non-respondents and the reason(s) for skipping questions was (were) probed for. The additional data resulted in a larger sample and was used to investigate the differences between respondents and non-respondents, whereas probing for the causes of missingness resulted in more knowledge about the nature of the missing data patterns.  相似文献   
106.
Logistic activity can be thought of as a socio-technical process whereby a social network of individuals orchestrates a series of technical activities using supporting systems such as transportation and communications. To understand the functioning of the entire system requires proper consideration of all its components. We identify seven key components: the objectives being pursued, the origin of the commodity flows to be transported, knowledge of demand, the decision-making structure, periodicity and volume of logistic activities, and the state of the social networks and supporting systems. Based on our analysis of the differences between commercial and humanitarian logistics, we pinpoint research gaps that need to be filled to enhance both the efficiency of humanitarian logistics and the realism of the mathematical models designed to support it.We argue that humanitarian logistics is too broad a field to fit neatly into a single definition of operational conditions. At one end of the spectrum we find humanitarian logistic efforts of the kind conducted in long-term disaster recovery and humanitarian assistance, where operational efficiency – akin to commercial logistics – is a prime consideration. At the other, post-disaster humanitarian logistic operations involved in disaster response and short-term recovery activities represent a vastly different operational environment, often in chaotic settings where urgent needs, life-or-death decisions and scarce resources are the norm. The huge contrast between these operational environments requires that they be treated separately.  相似文献   
107.
In a model where a monopolistic downstream firm (assembler) negotiates simultaneously with each of its intermediate‐input suppliers the prices of the complementary components which enter its product, we analyze the process by which the assembler separates from its suppliers as a Markov Perfect equilibrium. Due to a negative strategic effect (the prices and profits of independent suppliers decrease when their number increases), the assembler’s marginal return from keeping an upstream subsidiary is lower than the market value of an independent supplier. Separation is immediate when the downstream firm’s initial number of upstream subsidiaries is below a critical level. It is progressive in the reverse case and eventually leads to a mixed strategy whereby the assembler keeps all the remaining subsidiaries with some probability, and sells all them off in one go with the complementary probability.  相似文献   
108.
The authors examine theory and research on team intimacy and team cohesion, and argue that the two have often been confused, merged, and used interchangeably in recent theoretical, empirical, and applied work on team effectiveness. The authors propose distinct definitions to clarify and distinguish between team intimacy and team cohesion, and suggest areas that will aid research and application. Their examination provides a framework for understanding the inconsistent findings in team effectiveness and team building research and thus helps to improve human resource management (HRM) interventions.  相似文献   
109.
More diverse, perennial cropping systems often have better natural mechanisms for keeping pests at bay. But while scientists emphasise the broad benefits of conservation in terms of effective ecosystem functioning, farmers are more interested in biodiversity for the provision of food or of services such as shade or windbreaks. Because of their limited knowledge of the role of biodiversity in plant protection, farmers sometimes unconsciously disturb natural regulatory mechanisms. Some citrus farmers in Vietnam introduced sapodilla as an intercrop to diversify their source of income, and because this fruit tree requires little care. However, this apparently worthwhile attempt to combine two valuable crops has misfired. The ecological conditions that traditionally sustained natural pest control in citrus have been disturbed, thus trapping farmers in the pesticide treadmill. The weaver ant Oecophylla smaragdina stopped protecting citrus from stinkbugs and leaf-feeding caterpillars after facing competition from the black ant Dolichoderus thoracicus, which favours sapodilla trees as a nesting habitat. To avoid similar scenarios in the future, methods for linking scientific research on ecosystem functions with farmers' own knowledge, experience and priorities are presented. Examples are given of ways in which farmers in perennial cropping systems learn, and how scientists can facilitate this learning process.  相似文献   
110.
The impact of coding time on the estimation of school effects   总被引:1,自引:0,他引:1  
Multilevel growth curve models are becoming invaluable in educational research because they model changes in student outcomes efficiently. The coding of the time variable in these models plays a crucial role as illustrated in this study for the case of a three-level quadratic growth curve model. This paper shows clearly how the choice of a time coding affects school effects estimates and their interpretation. A new definition for school effects for growth curve models with random intercepts and slopes is proposed. This study recommends that the choice of a time coding should not only be based on the ease of interpretation and model convergence but also on its consequences on the student status and growth parameter estimates. The current application illustrates that in general the school effects for student growth in well-being and language achievement in secondary school, are greater for student growth than for student status.  相似文献   
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