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31.
In this paper we investigate the use of the structured full rank model for hedging the balance sheet of a financial institution. Simulation results suggest that the optimal hedge is insensitive to changes in parameter estimates. In addition, we hedge a portfolio of Treasury bills using both the full information covariance matrix and the structured covariance matrix. We then contrast these results with those obtained from a duration-based model. Empirical results suggest that the structured full rank model is generally more effective in hedging applications than either the full information model or duration-based model. 相似文献
32.
Milton D. Rosenau 《Journal of Product Innovation Management》1992,9(4):300-302
Too often companies fall into a trap when developing a list of performance specifications for a new product. Milton Rosenau calls this the best-of-the-best specification trap. The problem arises whenever a company bases a specification on the combination of the best single features observed in available competitive products. When this happens, the new product's design is driven by competition and is not derived from a unique market insight. This may not provide the basis for a sustainable advantage. Sometimes, rumors of competitive improvements may even lead to sudden changes in the specification, creating delays in the development process. A far better goal is to develop a specification that responds to an unrecognized and unfilled user need, one that adds high value to users. His points are illustrated with several examples. 相似文献
33.
D. P. Kennedy 《Mathematical Finance》1993,3(1):55-63
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
34.
Andrey D. Ukhov 《The Journal of Financial Research》2004,27(3):329-339
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
35.
36.
Sylvanus I. Ikhide 《The South African journal of economics. Suid-afrikaanse tydskrif vir ekonomie》2008,76(4):586-595
This paper examines the efficiency of commercial banks in Namibia using the standard econometric frontier approach. Although two aspects of efficiency (scale and scope) receive our attention, the emphasis is on the latter which pertains to whether a firm produces as efficiently as it possibly can, given its size. Our results indicate that substantial economies of scale exist in commercial banking in Namibia. This will tend to suggest that commercial banks in Namibia can increase their efficiency by increasing their current scale of operation. The results for scope economies show that the current level of input combination does not make for maximum efficiency as sufficient scope exists for a more efficient combination of inputs. We believe this will reduce operating costs in the industry and stimulate efficiency. 相似文献
37.
Bayesian MCMC Mapping of Quantitative Trait Loci in a Half-sib Design: a Graphical Model Perspective
N.A. Sheehan B. Gulbrandtsen M.S. Lund D.A. Sorensen 《Revue internationale de statistique》2002,70(2):241-267
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
38.
Nozer D. Singpurwalla 《Revue internationale de statistique》2002,70(1):53-65
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
39.
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
40.
Jonathan D. Linton Author Vitae 《Technological Forecasting and Social Change》2008,75(5):583-594
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