聚乙烯醇产品的市场研究

对聚乙烯醇树脂产品进行了产业背景、供求态势、市场细分与评估以及竞争力分析等全面研究，为聚乙烯醇项目建设、产品方案规划与市场营销提供决策参考。     

Option pricing in the presence of natural boundaries and a quadratic diffusion term

This paper uses a probabilistic change-of-numeraire technique to compute closed-form prices of European options to exchange one asset against another when the relative price of the underlying assets follows a diffusion process with natural boundaries and a quadratic diffusion coefficient. The paper shows in particular how to interpret the option price formula in terms of exercise probabilities which are calculated under the martingale measures associated with two specific numeraire portfolios. An application to the pricing of bond options and certain interest rate derivatives illustrates the main results.     

Calibrating an algorithm for estimating transactions from FXFX exchange rate quotes

In this paper we investigate the efficiency of a class of transaction-generating algorithms, originally suggested in Bollerslev and Domowitz (1993). Our comparison utilizes real transaction data recorded over Reuters D2000-2 electronic broking system for 7 h in June 1993 and transaction data generated from FXFX quotations over an identical period. Results suggest that, at this high-frequency data sampling, the performance of these transaction-generating algorithms is poor, with the most likely explanation of this outcome due to the high-frequency characteristics of FXFX spreads and quotation intensity.     

Estimating the credibility of an exchange rate target zone

Recent breakthroughs in the theory of exchange rate target zones have not been followed by similar contributions on the empirical side. The drift adjustment method of evaluating the credibility of a target zone has become common practice. However, the estimates of the expected rate of depreciation inside the band do not model knowledge of the band in the agents' information set. In this paper, a rational expectations limited-dependent variable method to estimate the expected rate of depreciation is used to remedy this weakness. In the case of the franc-mark target zone with daily data covering a 4-year period, we show that expected rates of devaluation of the order of 2.5% were still present in the early 1990s. Their reappearance in the autumn of 1992 may thus not be surprising.     

Central bank intervention and the volatility of foreign exchange rates: evidence from the options market

This paper tests the effects of central bank intervention on the ex ante volatility of $/DM and $/yen exchange rates between 1985 and 1991. In contrast to previous research which employed GARCH estimates of conditional volatility, we estimate ex ante volatility using the implied volatilities of currency option prices. We also control for the effects of other macroeconomic announcements. We find little support for the hypothesis that central bank intervention decreases expected exchange rate volatility. Instead, central bank intervention is generally associated with a positive change in ex ante exchange rate volatility, or with no change.     

Post Bretton Woods deviations from purchasing power parity in G7 exchange rates—an empirical exploration

Exchange rates have deviated substantially and idiosyncratically from purchasing power parity (PPP) since the breakdown of Bretton Woods. In this paper, a model incorporating both traditional PPP and financial market variables is constructed and tested on the US dollar's six G7 exchange rates during the floating rate era. Empirical tests show that the model's common set of variables—with consistent signs—can explain the divergent behavior of G7 exchange rates during 1973.2–90.2. Idiosyncracies are reflected in different subsets of the model's variables entering significantly into each exchange rate's regression; the existence of stable relationships is demonstrated by the equations' co-integration.     

Long term dependence in stock returns

We show, using the modified rescaled range statistic, that none of the return series of indices of five European countries, the United States and Japan exhibits long term dependence. This statistic — introduced by Lo (1991) — correct Hurst's (1951) ‘classical’ rescaled range statistic for short term dependence. We also report the classical rescaled range statistic after adjusting the series for short term dependence. This procedure shows, for cases where the results of the modified rescaled range statistic are mixed, that no long term dependence can be found. Simulations indicate reasonable power of this adjustment procedure. Furthermore, we find that estimates of the Hurst exponent, a related measure of long term dependence, are also biased by short term dependence. Simulations show that this measure — that has recently attracted growing interest — cannot distinguish between models with or without long term dependence.     

Revisiting the Miles and Snow strategic framework: uncovering interrelationships between strategic types,capabilities, environmental uncertainty,and firm performance

The Miles and Snow strategic type framework is re‐examined with respect to interrelationships with several theoretically relevant batteries of variables, including SBU strategic capabilities, environmental uncertainty, and performance. A newly developed constrained, multi‐objective, classification methodology is modified to empirically derive an alternative quantitative typology using survey data obtained from 709 firms in three countries (China, Japan, United States). We compare the Miles and Snow typology to the classification empirically derived utilizing this combinatorial optimization clustering procedure. With respect to both variable battery associations and objective statistical criteria, we show that the empirically derived solution clearly dominates the traditional P‐A‐D‐R typology of Miles and Snow. Implications and directions for future research are provided. Copyright © 2004 John Wiley & Sons, Ltd.     

Performance assessment of ensemble learning systems in financial data classification

Financial data classification plays an important role in investment and banking industry with the purpose to control default risk, improve cash and select the best customers. Ensemble learning and classification systems are becoming gradually more applied to classify financial data where outputs from different classification systems are combined. The objective of this research is to assess the relative performance of existing state‐of‐the‐art ensemble learning and classification systems with applications to corporate bankruptcy prediction and credit scoring. The considered ensemble systems include AdaBoost, LogitBoost, RUSBoost, subspace, and bagging ensemble system. The experimental results from three datasets: one is composed of quantitative attributes, one encompasses qualitative data, and another one combines both quantitative and qualitative attributes. By using ten‐fold cross‐validation method, the experimental results show that AdaBoost is effective in terms of low classification error, limited complexity, and short time processing of the data. In addition, the experimental results show that ensemble classification systems outperform existing models that were recently validated on the same databases. Therefore, ensemble classification system can be employed to increase the reliability and consistency of financial data classification task.     

湖北省乡村旅游资源分类与评价研究

乡村旅游是我国当前旅游发展的热点之一,乡村旅游资源分类与评价是合理开发、科学规划乡村旅游的基础。根据资源的价值和功能,构建了湖北省乡村旅游资源分类体系,包括8个主类,18个亚类,41个基本类型。湖北省乡村旅游资源特色突出,四季赏花资源丰富,千湖之省水乡风光典型,乡村文化深远且地域差异明显。在此基础上,提出了乡村旅游资源定量评价方法与标准,并对湖北省乡村旅游资源结构、等级、地域分布进行了评价,最后提出了湖北省乡村旅游发展的相关策略。