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1.
Replacement investment is essentially a regenerative optimal stopping problem; that is, the key decision concerns when to terminate the life of existing plant – and hence when to start over again. This paper examines this optimisation problem within a continuous time framework and studies the qualitative and quantitative impact of uncertainty on the timing of new investment (and the criteria that should be used for terminating the life of existing plant).  相似文献   
2.
This research extends the literature on nonfinancial performance measures (NFPMs) by assessing (1) the information content of a broader set of NFPMs and (2) whether NFPMs provide information not provided by financial performance measures (FPMs) from all previously identified FPM categories, rather than just earnings and book value. Specifically, exploratory and confirmatory factor analysis results presented in this paper demonstrate that nineteen NFPMs of major airlines capture seven underlying constructs not captured by eighteen common FPMs. Additionally, this research develops reliable composite measures of the identified performance measure constructs, which prior research argues are superior to individual performance measures.  相似文献   
3.
4.
This paper empirically examines the relationship between government foreign debt and the growth rate of per capita GDP based on a total sample of 77 countries, as well as sub‐samples of various regions. Cross‐sectional estimates of the coefficient of foreign debt based on the total sample have a negative sign, but are not always statistically significant. Available data from African countries indicate that foreign debt and the growth rate of per capita GDP were negatively related at a high level of significance. For industrialized and Latin American sub‐samples, this relationship is negative but statistically insignificant. The sub‐sample Asian and other developing countries show a positive but insignificant relationship. JEL classification: F34, H6, O23.  相似文献   
5.
The comparison of true cost of living indices between demographically different households (relative equivalence scale) is argued to be sensitive to the way demographic characteristics enter demand analysis. In particular, parameters reflecting the cost of demographic characteristics at base prices, though themselves do not have welfare (equivalence scale) interpretation, can alter the benchmark from which demographically varying inflation effects are measured. The empirical analysis, based on a rank‐3 demand system applied to UK individual household data, shows that the inflation adjustment of child benefits can vary with the way demographic costs at base period prices are specified.  相似文献   
6.
Nonstandard probability theory and stochastic analysis, as developed by Loeb, Anderson, and Keisler, has the attractive feature that it allows one to exploit combinatorial aspects of a well-understood discrete theory in a continuous setting. We illustrate this with an example taken from financial economics: a nonstandard construction of the well-known Black-Scholes option pricing model allows us to view the resulting object at the same time as both (the hyperfinite version of) the binomial Cox-Ross-Rubinstein model (that is, a hyperfinite geometric random walk) and the continuous model introduced by Black and Scholes (a geometric Brownian motion). Nonstandard methods provide a means of moving freely back and forth between the discrete and continuous points of view. This enables us to give an elementary derivation of the Black-Scholes option pricing formula from the corresponding formula for the binomial model. We also devise an intuitive but rigorous method for constructing self-financing hedge portfolios for various contingent claims, again using the explicit constructions available in the hyperfinite binomial model, to give the portfolio appropriate to the Black-Scholes model. Thus, nonstandard analysis provides a rigorous basis for the economists' intuitive notion that the Black-Scholes model contains a built-in version of the Cox-Ross-Rubinstein model.  相似文献   
7.
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   
8.
Many regions have experienced long-run economic fluctuations generated by the life cycles of their dominant industrial clusters. During the downswings in the 1970s and 1980s, proactive structural policies were typically launched in German regions to combat job losses in their core clusters and to create new jobs in new industries. With respect to the German State of Bremen, this paper provides empirical evidence of: (1) a long-run regional downswing; (2) the potential job effects of proactive regional industrial policy programmes in terms of increasing regional employment, by safeguarding jobs in the regional core industries and creating new jobs in new growth industries; and (3) a time pattern in the job effects, which are related to the different generations of programmes.  相似文献   
9.
设计了系统的基本思路,在Visual Studio 2008数据库的基础上,利用OpenGL对矿山巷道,硐室设计等进行三维可视化虚拟,并通过数学模型,对矿井设计进行分析与纠错处理,用C#实现系统的功能。  相似文献   
10.
We present a probabilistic model based on the one developed by Hernández Mendo and Anguera (Revista de Psicologíca Social, 16(1), 71–93, 2001). Here we have tried to break down the interaction contexts that the opposing teams are able to generate and transform during the game. We are aware that a given player or team does not produce consistent behaviour in similar situations. However, a degree of uncertainty is assumed to exist regarding whether the results obtained are a specific function of the analysis used. In order to carry out this research a category system which optimized that used in the previous model was developed. This system should enable the interaction between teams to be observed within the actual play of a soccer game. A lag sequential analysis was performed on the basis of a coding of the behavioural flow. After describing the behavioural patterns obtained a probabilistic model of the development of play in soccer is proposed.  相似文献   
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