Bayesian MCMC Mapping of Quantitative Trait Loci in a Half-sib Design: a Graphical Model Perspective

Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.     

IntraLATA long-distance demand: carrier choice, usage demand and price elasticities

Competition in the long-distance market in the US continues to intensify; the 1996 Telecommunications Act has led to increased competition in long-distance telephony especially as the Regional Bell Operating Companies have begun to gain entry to long-haul, long-distance markets. In order to better understand the implications of having increased service offerings, models of how customers choose between carriers (and the impact of this choice on subsequent usage) will be useful. We develop the first publicly available models that simultaneously estimate choice and usage for intraLATA long-distance in the US. Utilizing a generalized Tobit model, the price responsiveness of usage and carrier choice are estimated. The results are generally consistent with expectations both in terms of theory and of practical experience in the industry.     

Ambient Taxes Under m-Dimensional Choice Sets, Heterogeneous Expectations, and Risk-Aversion

We consider the design of ambient taxes forrisk-neutral and risk-averse polluters whenpolluters and the regulatory agency haveasymmetric information about environmentalrelationships and probabilities associatedwith random events. Unlike prior work, we showthat under these conditions, optimal ambienttaxes must be firm-specific, and accompaniedby additional incentives to influencepolluters' choices of abatement techniques.     

Wealth and Risk Effects of Adopting Deposit Insurance in Canada: Evidence of Risk Shifting by Banks and Trust Companies

This paper confirms that adopting explicit deposit insurance expanded risk-shifting incentives for Canadian Banks and Trust Companies. By transferring responsibility for monitoring non-systematic risk to the Canadian Deposit Insurance Corporation (CDIC), deposit insurance eliminated the compensation previously paid to large-block stockholder monitors. This transfer fueled a redistribution of insured-institution stock from poorly diversified large-block shareholders to diversified investors. Also, subsequent changes in market volatility support the hypothesis that CDIC insurance and the absorption of catastrophic risk it provided reduced systematic risk in the stock market as a whole even as it increased non-systematic risk in the banking and trust-company sector.     

Some Cracks in the Empire of Chance (Flaws in the Foundations of Reliability)

Making quantified statements about the uncertainty associated with the lifelength of an item is one of the most fundamental tasks of reliability assessment. Most practitioners routinely do this using one of the several available statistical techniques. The purpose of this paper is two-fold. The first is to give the user an overview of the key tenets of two of the most commonly used parametric approaches. The second is to point out that these commonly used approaches involve strategies that are either ad hoc, or are in violation of some of the underlying tenets. A method that is devoid of logical flaws can be proposed, but this method is difficult to implement. The user must therefore resign to using that technique against which the fewest objections can be hurled.     

Scaling up support for children in HIV-affected families by involving early childhood development workers: community views from KwaZulu-Natal,South Africa

The United Nations Programme on HIV/AIDS estimates that South Africa has 1.2 million orphans as a result of AIDS. This study investigated the views of communities in KwaZulu-Natal on the potential use of early childhood development (ECD) practitioners for helping children in vulnerable households. It reports on in-depth interviews and focus group discussions with community members and service providers in six different areas of KwaZulu-Natal. Despite the increase in the numbers of deaths, people in affected areas have yet to accept that HIV is the cause. Stigma, denial, myths and witchcraft beliefs were evident, particularly in the rural areas. There was general agreement by the respondents that ECD practitioners with additional training specific to HIV/AIDS could assist families if cost difficulties were overcome. As community members with basic training in childcare they could enhance community responses by linking with community health workers and other service providers to assist children and households in need.     

A theory of innovation for process-based innovations such as nanotechnology

Many see Nanotechnology as the technology that will underlie the next Schumpeterian wave creating new opportunities for wealth and job creation. Further it is a process based or materials technology. Yet all currently used models of innovation are based on assembled products or service products and these simply do not recognize the differences in materials products nor the “enabling” nature of Nanotechnologies. If nanotechnology is poised to become the economic engine of this millennium and if current models of innovation, which are utilized, by policy makers and firm based strategist alike are based on technology product paradigms that are dissimilar to the realities of nanotechnology and other process-based technologies then there is cause for concern.Here the authors provide a model and supporting cases demonstrating a new process or materials based innovation model that is based on the tight coupling between product and process innovation of not only Nanotechnology-based products but other process-based products. This is an important finding, because it identifies and remedies a gap in the literature associated with earlier process and product innovation models. For process-based products like materials, food, chemicals and nanotechnologies any change to the manufacturing processes results in significant changes in end product features. The implications of this model to practice are considered.     

Issues Facing Small Accounting Practices in Regional North Queensland: An Exploratory Study

Small accounting practices (SAP), most of which are sole principals, are an important part of the accounting profession and the Australian economy. This exploratory study identifies issues and challenges experienced by small accounting principals in Far North Queensland, Australia. The findings generally correspond with previous research, ranking staffing and keeping up to date through professional development as key areas of concern, and also highlighting the expectation gap between SAP principals and their clients. Stress emerged as a major concern for principals, and new areas of possible conflict of interests were uncovered. A number of potential areas for future research, including comparative studies in city and suburban areas, have been identified.     

Issues in Marketing Online Insurance Products: An Exploratory Look at Agents' Use, Attitudes, and Views of the Impact of the Internet

This article uses a survey of insurance agents in Florida to examine the manner in which insurance agents use and view the Internet as a method of marketing insurance products. The results of the survey suggest that the agents’ use of the Web and their attitudes toward the Web do not vary by demographic characteristics (including age, education level, gender, and income). In addition, the agents’ perception of the Internet as a threat (rather than an opportunity) does not vary by age or education level and is not correlated with their attitudes toward the use of the Web. However, while Internet marketing and other means of direct selling are viewed by the agents as equal threats to their sales, the agents believe that such marketing by other companies is a greater threat than that done by the companies they represent.     

Dividend Imputation and Shareholder Wealth: The Case of New Zealand

On April 1, 1988, New Zealand stopped the double taxation of dividends by implementing a full dividend imputation program. Because many believed that the tax advantage of debt had led to more highly leveraged firms subject to greater financial risk than was socially optimal, it was hoped the removal of incentives to finance with debt would result in a more efficient allocation of capital. The empirical results suggest that the shareholder wealth gain from dividend imputation was more than offset in firms with large debt levels. Moreover, an examination of debt ratios indicates debt levels declined in the post–imputation period.