The M/M\1 queue in a heavy-tailed random environment

We consider an M / M /1 queue with the special feature that the speed of the server alternates between two constant values s_L and s_H > s_L . The high-speed periods are exponentially distributed, and the low-speed periods have a regularly varying distribution. We obtain explicit asymptotics for the tail of the workload distribution. The two cases in which the offered traffic load is smaller respectively larger than the low service speed are shown to result in completely different asymptotics.     

External communication behaviour of purchasers—effects on supplier management performance

This article presents findings of a research effort that focuses on the relationships among the external communication behaviour of purchasers, individual and contextual factors and the performance in supplier management. Communication quantity, openness and friendliness were identified as dimensions of individual communication behaviour. Information and relationship quality were used as the two dimensions of communication quality. The results, based on structural equation analysis, provide support for the positive influence of individual communication behaviour on communication quality and supplier management performance. Results suggest that relationship quality appears to be of great significance in the model. Oral communication capability and purchasers’ attitudes towards individual communication with suppliers also play important roles in explaining external communication behaviour of purchasers.     

Discretionary fiscal policy and economic activity in Greece

This paper investigates the effects of discretionary fiscal policy changes on economic activity and its subcomponents in Greece in the period 2000–2011. Changes in government spending and net taxes have Keynesian effects. An increase in government consumption has the most pronounced positive effects on output growth, private consumption and non-residential investment, while it reduces residential investment. Cuts in the public investment programme crowd in private investment, but are associated negatively with the net exports ratio. Both indirect and direct tax hikes lower private consumption, private investment and output growth. However, higher direct taxes by lowering disposable income they reduce import demand, thus, improving the trade balance.     

Flexibility at different stages in the life cycle of projects: An empirical illustration of the “freedom to maneuver”

Many textbooks on project management present illustrations concerning the relative size of project attributes during different project phases. The derived models all have attributes in common, such as uncertainty, significance of decisions, and degree of freedom to maneuver, that are typically high in the beginning of the project and low in the end. At the same time, variables such as the accumulated cost and available information begin at low levels and end up at a high level at the end of the project. Based on empirical data from projects, this paper illustrates and quantifies one of these attributes, the freedom to maneuver, in different project phases.     

A Common Base Answer to the Question “Which Country Is Most Redistributive?”*

We believe that what most authors have in mind when referring to the “most redistributive country” is a tax and transfer schedule that is most redistributive across all pre-tax and transfer income distributions. In order to measure each country's tax and transfer redistribution according to the same baseline, we suggest using the transplant-and-compare method of Dardanoni and Lambert (2002, Journal of Public Economics 86, 99–122) to establish a common base. The redistributive effects of countries’ tax and transfer schedules are illustrated by employing microdata on eight countries from the Luxembourg Income Study (LIS). Of these eight countries, Finland is found to be the most redistributive country, according to the common base method.     

Carbon efficiency of US colleges and universities: a nonparametric assessment

Under the American College and University Presidents’ Climate Commitment (ACUPCC), institutes of higher education have pledged to pursue a goal of carbon neutrality. We utilize emissions reported under the ACUPCC agreement and a nonparametric data envelopment analysis approach in order to evaluate the relative performance of signatories to the agreement in terms of producing teaching and research with the least greenhouse gas emissions. We find that while many signatory institutions are now producing their desirable outputs relatively efficiently in terms of carbon emissions, there still exists considerable variation in efficiency and potential for improvement. Results of a second stage efficiency change analysis shows evidence of both movement towards the efficiency frontier since signing, and some movement of the frontier itself, though this evidence comes primarily from teaching-focused institutions.     

Did Hayek have a monetary theory of business cycles?

Joseph Schumpeter, a careful reader of Hayek, categorized Hayek??s theory of economic cycles as non-monetary. Almost every other source, including Hayek himself, categorized the theory as monetary. The issue turns on the concept of causality being used. The question of what causality concept to apply to complex phenomena has substantive implications for economic theory. A simple concept of causality, appropriate to the study of some physical phenomena, will mislead when applied to complex phenomena. We provide examples of errors in analysis that follow from the wrong choice of a causal paradigm.     

Optimal Management of Soil Quality Stocks and Long-Term Consequences of Land Degradation for Smallholder Farmers in Malawi

While soil degradation has long-term consequences, static models which form the bulk of studies on this topic in Africa, do not account for the inter-temporal dimensions of optimal resource management. This paper used an inter-temporal optimisation framework, which considered soil in a time-dependent resource extraction perspective. We have demonstrated that soil degradation is causing an enormous reduction in productive value of smallholder land in Malawi. Current user cost of soil quality among smallholder farmers, which represents annual loss in productive value of land, was estimated to be US$21 per hectare. Based on this value and land area under smallholder agriculture in Malawi, economic costs of soil degradation among smallholder farmers were estimated to amount to 14% of the agricultural GDP for Malawi. Although smallholder farmers’ current practices are sub-optimal to Steady State solutions, they are above static solutions. This demonstrates that smallholder farmers have some private incentives to invest in the soil quality stock. Smallholder farmers internalise some of the dynamic costs of soil degradation under the current practices. However, a sensitivity analysis on a slightly higher discount rate indicates that SS solutions closely resemble the prevailing smallholder farming practices. This suggests that smallholder farmers may be overexploiting soil quality stock because they have a high time preference. That is, they value the current consumption more than their future consumption and wellbeing. High levels of poverty in Malawi and serious lack of viable alternatives to subsistence farming may be influencing such behaviour. Promoting more viable land use alternatives than subsistence farming and formuling policies that help transform smallholder agriculture into a profitable enterprise will not only increase the cost of degrading the soil, but also encourage farmers to invest in the soil quality stock.     

Investigation of the Greek – Turkish Military Spending Relation

In this paper, the relation between the Greek and Turkish military spending is investigated, examining first the identification of its exact statistical form, and second, a diachronically constant ratio between the two magnitudes. Using annual nominal data over the period from 1949 to 2008, the stationarity of the series is tested by performing a sequential Augmented Dickey-Fuller (ADF) and a Kwiatkowski?CPhillips?CSchmidt?CShin (KPSS) unit root test. Both the long?Crun equilibrium relation among the series of the Greek and Turkish military spending and their diachronically constant ratio are estimated following a Johansen cointegration analysis.