Optimal harvesting under resource stock and price uncertainty

We analyze partial and complete depletion harvesting policy under resource stock and price uncertainty and risk neutrality. We state a set of weak conditions under which the optimal policy can be characterized by a single threshold and show that the value can be expressed in a separable form where price volatility affects the value through the risk adjusted growth rate. Both higher price and stock volatility decrease the value when the correlation between the driving Brownian motions is negative. With no correlation the optimal policy is independent of price volatility while higher stock volatility increases the harvesting threshold.     

A dynamic cournot-nash equilibrium in fishery: The effects of entry

A dynamic Cournot-Nash equilibrium of the fish war between two countries has been derived and its steady-state behavior studied by Levhari and Mirman on the basis of a discrete dynamic programming method. In this paper we shall consider an n-country extension of Levhari-Mirman fish war model. We shall derive the Cournot-Nash equilibrium and its steady-state value to analyze the effects of entry (or exit) in fish war. A comparison is made between in dividual management of fishery by each country and joint management by all countries.

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Riassunto In questo lavoro si considera l'estensione, al caso din paesi concorrenti, del modello concorrenziale dell'attività peschereccia proposto da Levhari e Mirman. Viene derivata la configurazione di equilibrio di Cournot-Nash e si calcola il suo valore stazionario per analizzare l'effetto d'entrata (o d'uscita) di un agente nella attività concorrenziale.Viene infine fatto un confronto tra la conduzione individuale della pesca in ogni singolo paese e la conduzione congiunta di tutti i paesi considerati.

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Versione definitiva pervenuta il 17-1-81     

The transfer of human resource management technology in Sino-U.S. cooperative ventures: Problems and solutions

Differences between Chinese and U.S. human resource management systems are described with respect to fundamental organization and work-related assumptions about people and performance, rewards, training and development, and educational background of HR practitioners. We identify key differences that present impediments to the modernization of HRM practices in Sino-U.S. cooperative ventures, and then, present a normative framework for the introduction of modem HRM practices into these ventures. We conclude with implications for both research and practice that focus primarily on integrating individuals and the enterprise, as well as integrating the enterprise with social and economic goals.     

The 2000 Presidential Election and the stock market

The impact of the delay in the declaration of a winner in the U.S. Presidential Election of 2000 on the performance of stock markets is examined in this study. We present evidence indicating that the stock market performance was different from a pre-event comparison period. Conventional t-tests and a dummy variable regression that controls for interest rate movements are used to present evidence indicating that there was a significant initial negative reaction to the delay in the election results. The authors thank Roy F. Cabaniss and Luellen A. Jones for editorial suggestions.     

股市第一案的罪与罚--从"中科创业操纵证券交易价格案" 看我国证券法律责任制度

2003年4月1日,北京市第二中级人民法院对有“中国股市第一案”之称的中科创业操纵证券交易价格案进行了一审公开宣判。这标志着我国反对股市黑幕进入了一个新的阶段。那么,法律是怎么审判“庄家”的?操纵证券交易价格应该承担什么样的责任呢?在股价操纵案中如何保护投资者的利益呢?……     

中国股票市场的月份效应

本文在概述其他学者研究成果的基础上,对我国股票市场的月份效应进行了检验和实证分析,结果发现我国股票市场上不存在许多其他成熟的和新兴的股票市场所共有的一月份效应,但却存在十二月份效应。本文对此进行了充分的论证,并进行了解释。     

Multiple patterns in the dynamics of a stock market model

We study a non-linear model of the interactions between stock market prices and the level of assets owned by investment funds. The model dynamics is described, in continuous time, by a smooth vector field in the plane, which presents, under suitable hypotheses, a unique equilibrium point.Our analisis of the system flow is qualitative and focuses on detecting endogenous fluctuations of the state variables, i.e. on checking existence and number of limit cycles.We prove that several, and quite different, dynamical patterns can occur, even in cases where the system isoclines assume that most simple geometrical forms.It is shown, in particular, that the equilibrium point can undergo either a sub-critical or a super-critical Hopf-bifurcation whenever two economically meaningful exogenous parameters are made to cross a given set of critical values. Hence, in the subcritical case, as a trapping region exists, at least two limit cycles appear.Next, we give analytical examples of model-consistent vector fields which present a multiplicity of fluctuating trends, and prove the apparently surprising result that the number of limit cycles can be as large as one wants, provided a specific isocline assumes a cubic shape.Both authors are members of the Gruppo Nazionale per l'Analisi Funzionale e le sue Applicazioni-G.N.A.F.A. of the Italian Council of Researches-CN.R.The present paper refers to the activities of the National M.U.R.S.T. Group Dinamiche Non Lineari ed Applicazioni alle Scienze Economiche e Sociali.     

Long-term reactions to large stock price declines and increases in the European stock market: a note on market efficiency

This study tests for underreaction and overreaction in European large cap markets by examining the abnormal returns of those stocks in the EuroStoxx 50 Index following large price increases and decreases. We find that large price increases and declines tend to be followed by average market returns. Thus, our results support the efficient market theory, rather than any of the behaviour finance hypotheses. This insight is contrary to price patterns found in various national markets.     

香港创业板给我们带来的启示

国内二板市场的酝酿时间超过了4年,迄今尚未推出,但晚有晚的好处,可以使我们有充分的时间把即将推出的二板市场搞的更加成熟,同时,借鉴一下香港创业板的成功与不足,无疑对我们是非常有益的.     

The pricing of callable preferred stock

In this study, the authors use both the Black/Scholes European option model and the Barone-Adesi/Whaley American option model to estimate call option values implicit in seasoned callable preferred stock issues. Consistent with the finding that call features increase bond yields, a significant relationship is found between estimated option values and discounts of these securities’ market prices from their estimated income values. However, the size of the discount is only a fraction of what would be predicted by the American option model. Specifically, the market does not appear to take the “early exercise premium” into account. Furthermore, this discount seems to be isolated to in-the-money call features that have evolved to their final call price. Thus, incorporation of a call feature into a security’s indentures, with a deferment period and an initial premium call price, appears to represent a pure gain for the issuing corporation.     

The design of executive stock options

A contract between manager and shareholder comprising salary plus options which are sometimes out of the money implies less risky managerial income but weaker incentives than a contract comprising salary plus stocks (or options which are always in the money) which leaves the manager as well off. Increasing the exercise Price and the salary so that (1) there are some states where the options cannot be exercised but (2) the manager is as well off as before always leads initially to a reduction in effort which outweighs any gains from improved risk sharing, leaving the shareholder worse off.     

The Heisenberg picture in the analysis of stock markets and in other sociological contexts

We review some recent results concerning some toy models of stock markets. Our models are suggested by the discrete nature of the number of shares and of the cash which are exchanged in a real market, and by the existence of conserved quantities, like the total number of shares or some linear combination of the cash and the shares. This suggests to use the same tools used in quantum mechanics and, in particular, the Heisenberg picture to describe the time behavior of the portfolio of each trader. We finally propose the use of this same framework in other sociological contexts.     

The VIX,the variance premium and stock market volatility

We decompose the squared VIX index, derived from US S&P500 options prices, into the conditional variance of stock returns and the equity variance premium. We evaluate a plethora of state-of-the-art volatility forecasting models to produce an accurate measure of the conditional variance. We then examine the predictive power of the VIX and its two components for stock market returns, economic activity and financial instability. The variance premium predicts stock returns while the conditional stock market variance predicts economic activity and has a relatively higher predictive power for financial instability than does the variance premium.     

我国干旱地区在城市中实施集雨工程势在必行

我国西北黄土高原丘陵沟壑区、华北干旱缺水山丘区、西南旱山区主要涉及 13个省 (市、自治区 ) ,74 2个县 (市 ) ,面积约 2 0 0万平方公里 ,人口约 2 6亿。水资源贫乏 ,区域性、季节性干旱缺水城市更为严重 ,地下水超采严重 ,水位下降 ,地面下沉。急需将集雨工程引入城市。可首先引入城市的绿化工程中来 ,绿化地面应低于硬化地面 ,节水和绿化应有机地统一起来 ,使天然降雨这个潜力巨大的水资源得到有效的利用。     

Risk and return in the Tehran stock exchange

This paper analyzes market index returns in the Tehran stock exchange (TSE) within the context of three variants of the Capital Asset Pricing Model: the static international; the constant-parameter intertemporal; and a Markov-switching intertemporal CAPM, which allows for time-varying degree of integration with regional and international equity markets. We find that TSE returns are CAPM-efficient at monthly frequency with respect to several international market indices. Moreover, we find evidence in support of international integration of the TSE with respect to international markets. In addition, we conduct an extensive investigation for the direction of causality between TSE returns, international market index returns, and those in neighboring countries.     

The effects of uncertainty on investment and the expected long-run capital stock

This paper examines the effects of output price uncertainty on the optimal investment behavior of a risk-neutral competitive firm with a constant returns to scale production function. In the presence of convex costs of adjustment, investment is an increasing function of q, the shadow price of capital. Given the current price of output, we find that increased uncertainty will raise the current rate of investment. Increased uncertainty will also increase the expected long-run capital stock if the price of output is serially uncorrelated. However, if the price of output is serially correlated, then the direction of the effect of increased uncertainty on the expected long-run capital stock depends on the curvature of the marginal adjustment cost function. In this case, we obtain results which are directly opposite of the results in the literature and we locate the flaw in the existing analysis.     

Thinning and harvesting in stochastic forest models

This paper analyzes a stochastic forest growth model in which the manager is able to first thin the forest to promote better growth before harvesting. Both Wicksell single thinning and harvesting cycle and Faustmann on-going rotation problems are considered. The Wicksell problem is analyzed by first restricting the class of decision times to (thinning, harvesting) pairs that bound the growth away from infinity and imbedding the problem in an infinite-dimensional linear program on a space of triplets of measures. These measures capture the thinning and harvesting decisions along with the behavior of the growth process prior to harvest. An auxiliary linear program then leads to a nonlinear optimization problem for which an optimal value and solution are determined. The values of all the problems are be related through a set of inequalities. The solution of the nonlinear problem determines (random) thinning and harvesting times for the single thinning and harvesting cycle which demonstrate the equality of the values of these various problems. Finally for the Wicksell problem, the unrestricted class of thinning and harvest times is shown to give the same value as the restricted class. The Faustmann on-going thinning and harvesting rotation problem is reduced to a Wicksell problem which then allows for the characterization of the value as the solution to a different nonlinear optimization problem. The effects of the opportunity to thin the forest are illustrated on a mean-reverting stochastic model.     

城市资本存量模型分析

文章研究城市资本市场中资本存量的问题,建立了城市人均资本存量模型,反映了资本存量与各影响因素的相关关系.利用该模型对上海市的人均资本存量进行了分析.该模型具有预测作用,有助于城市管理主体制定城市发展政策.     

实施股票期权激励相关问题思考

本文基于国内公司实施股票期权激励的政策环境,分析了中国联通实施股票期权激励的案例,提出了实施股票期权激励在操作层面应掌握的相关问题,旨在为拟实施股票期权激励的公司提供借鉴.     

The day of the week effect on stock market volatility

This study tests the presence of the day of the week effect on stock market volatility by using the S&P 500 market index during the period of January 1973 and October 1997. The findings shown that the day of the week effect is present in both volatility and return equations. While the highest and lowest returns are observed on Wednesday and Monday, the highest and the lowest volatility are observed on Friday and Wednesday, respectively. Further investigation of sub-periods reinforces our findings that the volatility pattern across the days of the week is statistically different.(JEL G10, G12, C22)