Extreme volatility,speculative efficiency,and the hedging effectiveness of the oil futures markets

This study investigates the efficiency of the New York Mercantile Exchange (NYMEX) Division light sweet crude oil futures contract market during recent periods of extreme conditional volatility. Crude oil futures contract prices are found to be cointegrated with spot prices and unbiased predictors of future spot prices, including the period prior to the onset of the Iraqi war and until the formation of the new Iraqi government in April 2005. Both futures and spot prices exhibit asymmetric volatility characteristics. Hedging performance is improved when asymmetries are accounted for. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:61–84, 2007     

Collaborative Requirements Elicitation: A Process-Centred Approach

Requirements Elicitation is one of the first and most critical processes in system engineering. In this paper we will focus on the collaborative aspects of requirement elicitation, in the context of system development. To do so, we adopted the separation of concerns method. Using this method we separate engineering aspects from collaboration aspects in order to study both aspects and finally integrate them. For the collaborative aspect of requirements elicitation we looked at Collaboration Engineering. Collaboration Engineering is an approach to design and deploy processes for recurring collaborative tasks that can be transferred to practitioners to execute for themselves without intervention of professional facilitators. From an engineering perspective we will use the requirements engineering processes described by system engineering standard EIA-632 as a starting point. To integrate these we will use methods and techniques from Collaboration Engineering to specify the collaborative processes involved in this requirements elicitation approach. An object model was build using Unified Modelling Language. This model shows different concepts underlying our approach. Finally two case studies are presented to evaluate this approach.     

Modeling producer responses with dynamic programming: a case for adaptive crop management

Past research found agricultural producers’ conditional responses during the growing season are important adaptations to weather and other stochastic events. Failing to recognize these responses overstates the risks confronting producers and understates their ability to respond to adverse circumstances. Dynamic programming (DP) provides a means for determining optimal long‐term crop management plans. However, most applications in the literature base their analysis on annual time steps with fixed strategies within the year, effectively ignoring conditional responses during the year. We suggest an alternative approach that captures the strategic responses within a cropping season to random weather variables as they unfold, reflecting farmers’ ability to adapt to weather realizations. We illustrate our approach by applying it to a typical cereal farm in Karak, Jordan. The results show that including conditional within‐year responses to weather reduces the frequency of fallowing by 23% and increases expected income by 9%.     

Making Globalization Inclusive: Job Creation and Wage Inequality in Developing Economies

Open Economies Review -     

Towards a Democratic New Normal? Investor Reactions to Interim-Regime Dominance during Violent Events

Although interim regimes in former autocracies are generally tasked with initiating a democratic ‘new normal’, they may privately intend to become their country’s new autocratic rulers. We argue that, to cope with the uncertainty stemming from this possibility, investors infer an interim regime’s intentions from the dominance displayed by the regime during government-related violence, as reflected in the share of civilian fatalities. Specifically, we propose that investors interpret higher interim-regime dominance as a signal of weaker democratic intentions and associate such weaker intentions with a gloomier political outlook for local firms. We therefore hypothesize that investors react more negatively to violent events characterized by higher interim-regime dominance. We also hypothesize a less negative effect of such dominance for firms with larger foreign footprints, lower indebtedness, or more concentrated ownership, since investors will likely consider such firms more resilient to political deterioration. Applying event study methodology to 94 spells of violence in Egypt during the Arab Spring, we find substantial support for our hypotheses, thus contributing to management research on investor decision-making, violence, and political uncertainty.     

Natural disasters and countries' exports: New insights from a new (and an old) database

This paper is the first to uncover in details the impact of different families of disasters on exports from 1979 to 2000 (storms, floods, earthquakes and changes in temperatures). Besides, our paper is the first to compare in a quasi‐systematic way the results across the two data sets at hand, the standard EM‐DAT data and GeoMet data, a newly available data set based on geophysical and meteorological data (European Economic Review, 2013, 58, 18; Journal of Development Economics, 2014, 111, 92). We run series of regressions while accounting progressively for the characteristics of products (all traded goods v/s agriculture ones), the characteristics of the country (size, level of development) and the intensity of the catastrophes. When pooling all countries, and all types of disasters, we do not find any statistical impact on exports. But when focusing on each of them separately and on agricultural goods, the occurrence of an earthquake appears to reduce exports of about 3%, regardless of its location. A windstorm shock, even when it happens to be very severe, has hardly any impact. A flood, on its side, is estimated to reduce export flows of a small country by nearly 3%. The effect of changes in temperatures is ambiguous. All in all, except for temperature‐related disasters, the results are consistent across both data sets, EM‐DAT and GeoMet, although they appear to be slightly more in line with our expectations in the case of GeoMet.     

Unit root and trend breaks in per capita output: evidence from sub-Saharan African countries

This article examines the nonstationary properties of per capita real output in 28 sub-Saharan African (SSA) countries, covering the period 1960–2014. The sequential testing approach proposed by Kejriwal and Lopez (2013, Econometric Reviews 32(8), 892–927) is used to categorize SSA countries into growth shift, level shift and linear trend hypotheses based on the presence or not of breaks in slope and/or level of the trend function. The break dates are associated to major historical or economic events such as sociopolitical crisis, commodity price fluctuations on international market, the discovery and the exploitation of mineral deposits or unfavourable environmental and climatic conditions. The empirical evidences of appropriate unit root tests fail to reject the unit root hypothesis in all the countries, suggesting that a shock would have a permanent effect on growth process, and stabilization policies may be implemented in dealing with income fluctuations.     

Suggestie betreffende het combineren van overschrijdingskansen

Summary In this paper a new method for combining P -values is suggested. This method takes into account that the P-values to be combined may be based upon different numbers of degrees of freedom.