Exact Ruin Probabilities and the Evaluation of Program Trading On Financial Markets

For a compound Poisson process with negative drift and jump distribution consisting of a mixture of exponentials on [0) and on (-, 0), an exact expression is derived for the probability of hitting the level c, c > 0. the problem is motivated by modeling the returns from trading on financial markets.     

An extension of mixed estimation,with an application to forecasting new product growth

This paper extends the mixed estimation technique to handle a case in which the coefficients of a set of linear constraints are known nonlinear functions of an unknown parameter vector for which an extraneous unbiased estimate is available. This novel form of the mixed estimation technique is illustrated by applying it to the Bass innovation/diffusion model of new product growth. It is suggested that this is superior to the traditional method whereby managerial intuition is incorporated into this type of model, and is an attractive alternative to recently-suggested Bayesian methods.I thank an anonymous referee for helpful comments and references.     

Finding a lasting cure for U.S. health care

In "Making Competition in Health Care Work" (July-August 1994), Elizabeth Olmsted Teisberg, Michael E. Porter, and Gregory B. Brown ask a question that has been absent from the national debate on health care reform: How can the United States achieve sustained cost reductions while at the same time maintaining quality of care? The authors argue that innovation driven by rigorous competition is the key to successful reform. A lasting cure for health care in the United States should include four basic elements: corrected incentives to spur productive competition, universal insurance to secure economic efficiency, relevant information to ensure meaningful choice, and innovation to guarantee dynamic improvement. In this issue's Perspectives section, eleven experts examine the current state of the health care system and offer their views on the shape that reform should take. Some excerpts: "On the road to innovation, let us not forget to develop the tools that allow physicians, payers, and patients to make better decisions." I. Steven Udvarhelyi; "Health care is not a product or service that can be standardized, packaged, marketed, or adequately judged by consumers according to quality and price." Arnold S. Relman; "Just as antitrust laws are the wise restraints that make competition free in other sectors of the economy, so the right kind of managed competition can work well in health care." Edward M. Kennedy "Biomedical research should be considered primarily an investment in the national economic well-being with additional humanitarian benefits." Elizabeth Marincola.     

Attilla the Hun: leadership as a change agent

This presentation will examine both ideas and successful examples of how some companies are inspiring and empowering their employees through the development of leadership skills within their management ranks. These skills can be learned and used to aid any organization in its goal of continuous improvement. Today's leadership establishes corporate directions while balancing individual and group achievement, both of which can improve the overall company. Power is shared, not used to control. After all, leadership is not about power. It is about setting directions for others, the clearing of obstacles, and then allowing others to believe the direction was their idea. Great leadership is based on the success of others.     

Classical Swine Fever Changes the Way Farmers Value Pigs in South Africa

Although there is growing demand for animal products in Africa, production is stagnating. Appropriate management of livestock diversity could help reinvigorate production, contribute to food security and improve farmers’ livelihoods, particularly in subsistence‐oriented systems. We assess differences in farmers’ preferences and economic values for pig traits across different production systems and across areas that have been affected and unaffected by classical swine fever (CSF). Not surprisingly, market‐oriented farmers derived higher values from the productive traits such as heavy slaughter weight and large litter size found in exotic pig genotypes. Subsistence‐oriented farmers, particularly in swine fever affected areas, placed high value on tolerance to disease. We found that CSF changed farmers’ preferences for adaptive traits, and less so for productive traits. Therefore, indigenous breeds become more valuable for subsistence farmers and crossbreeds for market‐oriented farmers if CSF is a risk. Our results can have implications for breeding and conservation strategies and for compensation strategies after culling, and will become increasingly relevant if, as predicted, heat waves and disease outbreaks become more frequent in pig production systems in South Africa with climate change.     

选举提名方式与土地管理体制:村民对村领导行为及其绩效的评价

提名方式是选举的重要组成部分 ,农村民主选举的不同提名方式对村领导的行为及其绩效有不同的影响。对土地的投入是农村普遍的经济活动 ,与土地相关的活动对村民来说是至关重要的 ,村民对村领导决定的土地分配有着强烈的反响。从农村民主选举与土地管理体制的角度来研究选举提名方式是农村民主政治建设研究的一个新视角。     

Predicting Corporate Failure Using a Neural Network Approach

This paper investigates the performance of Artificial Neural Networks for the classification and subsequent prediction of business entities into failed and non-failed classes. Two techniques, back-propagation and Optimal Estimation Theory (OET), are used to train the neural networks to predict bankruptcy filings. The data are drawn from Compustat data tapes representing a cross-section of industries. The results obtained with the neural networks are compared with other well-known bankruptcy prediction techniques such as discriminant analysis, probit and logit, as well as against benchmarks provided by directly applying the bankruptcy prediction models developed by Altman (1968) and Ohlson (1980) to our data set. We control the degree of ‘disproportionate sampling’ by creating ‘training’ and ‘testing’ populations with proportions of bankrupt firms ranging from 1% to 50%. For each population, we apply each technique 50 times to determine stable accuracy rates in terms of Type I, Type II and Total Error. We show that the performance of various classification techniques, in terms of their classification errors, depends on the proportions of bankrupt firms in the training and testing data sets, the variables used in the models, and assumptions about the relative costs of Type I and Type II errors. The neural network solutions do not achieve the ‘magical’ results that literature in this field often promises, although there are notable 'pockets' of superior performance by the neural networks, depending on particular combinations of proportions of bankrupt firms in training and testing data sets and assumptions about the relative costs of Type I and Type II errors. However, since we tested only one architecture for the neural network, it will be necessary to investigate potential improvements in neural network performance through systematic changes in neural network architecture.