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31.
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.  相似文献   
32.
The classical warrant pricing formula requires knowledge of the firm value and of the firm‐value process variance. When warrants are outstanding, the firm value itself is a function of the warrant price. Firm value and firm‐value variance are then unobservable variables. I develop an algorithm for pricing warrants using stock prices, an observable variable, and stock return variance. The method also enables estimation of firm‐value variance. A proof of existence of the solution is provided.  相似文献   
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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.  相似文献   
36.
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.  相似文献   
37.
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.  相似文献   
38.
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.  相似文献   
39.
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.  相似文献   
40.
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.  相似文献   
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