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61.
Managing Price Risk in the Pakistan Wheat Market 总被引:1,自引:0,他引:1
The government intervenes in the wheat market in Pakistan toensure food security for consumers and to provide adequate andstable incomes for producers. The cost of this interventionis high, and its impact on the performance of agriculture hasbeen significantly negative. The World Bank is urging policychanges such as removing agricultural trade restrictions, pricesupports, and subsidies. However, policymakers often resistsuch reforms, fearing that they will expose the domestic marketto fluctuating international commodity prices. This article assesses the risk management needs of the sectorand evaluates whether using financial instrumentssuchas commodity hedging using futures, options, or swapswouldimprove risk management. Simulations based on monthly data for1994 show that market-based methods of risk management couldreduce the impact of international price volatility on the domesticmarket without incurring high government cost or distortingprice signals. 相似文献
62.
This study examines the influence of day-of-the-week patterns in security returns on long-run IPO underperformance. Comparisons are made between the IPOs in Ritter's [20] database, and a constructed set of matching firms based on SIC code and size, using NYSE, AMEX, and NASDAQ securities. It is found that virtually all of the IPO underperformance occurs on Mondays and Tuesdays and that the degree of underperformance significantly differs from other days. Thus, a common explanation may exist for the general day-of-the-week pattern in security returns and IPO long-run underperformance. 相似文献
63.
Xu You-heng Dong Li-yun Huang Dong-qun Fudan University Shanghai P. R. China 《水动力学研究与进展(B辑)》1998,(3)
In this paper,the oscillation amplitude of the free end of a group of threecylinders are studied.The three cylinders are erected at the vertices of an equilateral trian-gle,and three arrangements are made in this study.One of the three cylinders is served asa working cylinder which is mounted by a flexible cantilever and two accelerometers areattached on the free end in two directions.The results of the three-cylinder arrangementare compared with those of two cylinders in tandem/side-by-side arrangement in the samecondition.The experimental results show that the rear cylinder of a group of three cylin-ders is affected more seriously than that of the corresponding two cylinders in the contrastarrangement.The main direction of oscillation is changed.The transversal oscillation isstronger than the longitudinal oscillation in the three-cylinder arrangement.On the con-trary,the transversal oscillation is much weaker than the longitudinal oscillation in two-cylinder arrangement.The largest transversal oscillat 相似文献
64.
This report looks at evaluation studies of a number of cooperative academic-industrfy research programmes in Europe, and suggests that indirect economic benefits should be taken into account as well as motives and goals of participating firms. 相似文献
65.
66.
A conceptual framework of anonymity in Group Support Systems 总被引:2,自引:2,他引:0
Joseph S. Valacich Leonard M. Jessup Alan R. Dennis J. F. Nunamaker Jr. 《Group Decision and Negotiation》1992,1(3):219-241
As the development and use of automated systems for collaborative work grows, the need for a better understanding of these systems becomes more important. Our focus is on one type of system, a Group Support System (GSS) and, in particular, on one important aspect of a GSS—anonymity. A conceptual framework for the study of anonymity in a GSS is presented, which describes the general classes of variables and their relationships. These variables include the factors that influence anonymity in a GSS, types of anonymity, and the effects of anonymity on a message sender, receiver, group process, and outcome. Each of these variables is discussed with working propositions presented for important group process and outcome measures. The objectives of this article are to highlight the importance and complexity of anonymity, to act as a guide for empirical investigations of anonymity, and to influence future GSS development and use. 相似文献
67.
William R. Dillon Ulf Böckenholt Melinda Smith de Borrero Ham Bozdogan Wayne de Sarbo Sunil Gupta Wagner Kamakura Ajith Kumar Benkatram Ramaswamy Michael Zenor 《Marketing Letters》1994,5(4):323-334
Our paper provides a brief review and summary of issues and advances in the use of latent structure and other finite mixture models in the analysis of choice data. Focus is directed to three primary areas: (1) estimation and computational issues, (2) specification and interpretation issues, and (3) future research issues. We comment on what latent structure models have promised, what has been, to date, delivered, and what we should look forward to in the future. 相似文献
68.
Daniel R. Denison Jane E. Dutton Joel A. Kahn Stuart L. Hart 《Journal of Management Studies》1996,33(4):453-474
This paper explores the relationship between organizational context and the interpretation of strategic issues by examining the hypothesis that CEOs' interpretations of foreign investment in the USA are influenced by the organizational context in which they are embedded. Three aspects of organizational context - the global business experience of the firm; the firm's level of organizational inertia (as represented by firm age and size); and the resources available for responding - are examined as predictors of CEOs' perceptions of foreign investment as a threat or an opportunity. Analysis of data from 320 organizations, controlled by industry, shows that global business experience, firm size, and perceived capability are significant predictors of the perception of threat and opportunity. the discussion addresses the implications of these findings for future research on issue interpretation and organizational context. 相似文献
69.
In this paper we offer a method for deciding how to aggregate a set of elementary industries. The method is then applied to the problem of estimating a wage equation that allows for industry-specific effects. Our method explicitly formalizes the trade-off between goodness-of-fit and parsimony implicit in an aggregation problem. By varying the parameter of the assumed loss function, one obtains a whole sequence of aggregation levels. Further, the resulting sequence is consistent; that is, groupings formed at one level of aggregation will never be undone when one aggregates further. 相似文献
70.
Endocrine disrupting chemicals (EDCs) are the focus of current environmental issues, as they can cause adverse health effects to animals and human, subsequent to endocrine function. The objective of this study was to remove a specific compound of EDCs (i.e. pentachlorophenol, C(6)OCL(5)Na, molecular weight of 288 g/mol) using low pressure reverse osmosis membrane (LPROM). A cross flow module of LPROM was used to observe the effects of operating parameters, i.e. pH, operating pressure and temperature. The design of the experiment was based on MINITAB(TM) software, and the analysis of results was conducted by factorial analysis. It was found that the rejection of pentachlorophenol was higher than 80% at a recovery rate of 60 to 70%. The rejection was subjected to increase with the increase of pH. The flux was observed to be increased with the increase of operating pressure and temperature. This study also investigated the interaction effects between operating parameters involved. 相似文献