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61.
Unlike the traditional futures contract risk‐based approach to margining, new security futures contracts are margined under a strategy‐based margining system similar to that which applies in the equity options markets. As a result, these new margin requirements are potentially much less sensitive to changes in market conditions. This article performs a simulation to evaluate whether these alternative margining methodologies can be expected to produce comparable outcomes. The analysis suggests that a 1‐day settlement period will likely lead to collection of customer margins that are virtually always greater than that which its traditional risk‐based counterpart would require. A 4‐day settlement period would lead to margin requirements that both significantly under‐ and overmargin relative to a comparable risk‐based system. This study argues that exchanges may approach the preferred probability of customer exhaustion by managing margin settlement intervals. Thus, the new strategy‐based rules, in and of themselves, will not necessarily inhibit new security futures trading activity. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:989–1002, 2003  相似文献   
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A model to simulate the costs and returns of an individual dairy cow over 14 years under various assumptions of genetic potential, health status and management was developed especially to evaluate the effects of diseases that reduce production and reproduction efficiency and to evaluate alternative management interventions. Data were collected from the Food Animal Health Resource Management System (FAHRMX), Today's Electronic Planning (TELPLAN), Today's Electric Farm Accounting (TELFARM) databases and secondary sources at Michigan State University. A case study of cystic ovaries was analysed using the model. The results showed that it is more economical to treat cystic ovaries than not to treat, and treatment with Gonadotropin Releasing Hormone (GNRH) was superior to Human Chrionic Gonadotropin (HCG). Four to five lactations were the optimum for keeping a dairy cow to replacement and it was estimated that there is a loss of US$0.45 per day of extended calving interval (days open beyond the optimal 70 days).  相似文献   
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Estimation in the interval censoring model is considered. A class of smooth functionals is introduced, of which the mean is an example. The asymptotic information lower bound for such functionals can be represented as an inner product of two functions. In case 1, i.e. one observation time per unobservable event time, both functions can be given explicitly. We mainly consider case 2, with two observation times for each unobservable event time, in the situation that the observation times can not become arbitrarily close to each other. For case 2, one of the functions in the inner product can only be given implicitly as solution to a Fredholm integral equation. We study properties of this solution and, in a sequel to this paper, prove that the nonparametric maximum likelihood estimator of the functional asymptotically reaches the information lower bound.  相似文献   
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An extensive collection of continuous-time models of the short-term interest rate is evaluated over data sets that have appeared previously in the literature. The analysis, which uses the simulated maximum likelihood procedure proposed by Durham and Gallant (2002), provides new insights regarding several previously unresolved questions. For single factor models, I find that the volatility, not the drift, is the critical component in model specification. Allowing for additional flexibility beyond a constant term in the drift provides negligible benefit. While constant drift would appear to imply that the short rate is nonstationary, in fact, stationarity is volatility-induced. The simple constant elasticity of volatility model fits weekly observations of the three-month Treasury bill rate remarkably well but is easily rejected when compared with more flexible volatility specifications over daily data. The methodology of Durham and Gallant can also be used to estimate stochastic volatility models. While adding the latent volatility component provides a large improvement in the likelihood for the physical process, it does little to improve bond-pricing performance.  相似文献   
66.
Hall and Miles (1990) suggest an approach of estimating default probabilities of banks using stock market information, and in this paper we apply an aggregated version of their approach to banking sectors around the world in both developed and emerging economies. We study the market’s assessment of the probability of systemic banking crises world wide over the last decade, including the Asian crisis 1997–1998. In addition, we investigate whether there is a relationship between the failure probability and institutional features of the actual banking sector. The quality of governance and the degree of law and order in a country is found to be significantly negatively related to the market based failure probabilities as is an explicit deposit insurance during periods of crisis.  相似文献   
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Cash settlement of derivative contracts makes them susceptible to manipulation by traders who expect to close large positions upon final settlement. Cash settlement also increases underlying volatility when hedgers unwind their hedges if they have no incentives to control their trading costs. Limits on the positions that traders can carry into final settlement can be used to mitigate associated economic inefficiencies when surveillance is insufficient. This article develops a model that regulators can use to set these limits that is based upon microstructure theory. The empirical findings indicate that existing position limits are largely inconsistent with those suggested by the model. © 2005 Wiley Periodicals, Inc. Jrl Fut Mark 25:945–965, 2005  相似文献   
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