Centralized and decentralized control polices for a two-stage stochastic supply chain with subcontracting

An analysis of control policies for a two-stage supply chain with subcontractors at each stage is presented when decisions at each stage concerning safety stocks, backorders, and subcontracting are made jointly or in a decentralized manner. The inventory/admission control policies considered are base stock, echelon base stock and partial backordering, and the objective is to maximize the mean profit rate of the system. The optimal control parameters are found by exhaustive search using Markov chains. From numerical examples it appears that the policies which manage jointly sales and production levels in each stage provide much higher overall (system) profits than decentralized policies, although the latter are individually more profitable for the second stage. In addition, partial backordering provides the system with an extra profit above those that result from the lost sales (no backordering) and complete backordering policies. Finally, a number of numerical results show the impact of variations in certain system parameters on the optimal control parameters and the corresponding profit.     

Comparative assessment of tourist generating markets for New Zealand

Portfolio analysis has become a widely used strategic planning tool in many industries during the past decade. Strategic decisions in the tourism industry include issues such as which markets are most attractive (e.g. have greatest visitor expenditure potential); in which markets are a specific country's “products” most competitive; how promotional budgets should be allocated for greatest effectiveness; and what the promotional message should convey. Industry Attractiveness Analysis—a flexible variety of portfolio analysis—has been applied to the generating countries which supply tourists to New Zealand in an illustrative case study. Both national level and individual company applications are described and illustrated in 3 × 3 matrix form. These diagrams are, in themselves, a good communication mechanism which encourages rational, strategic thinking about managerial decisions and resources allocations. Past, present, and future situations can be portrayed in a graphically useful manner.     

The Biofuel Controversy

Summary  About a decade ago, the main OECD countries decided to promote the use of biofuels so as to reduce greenhouse gases, to contribute to energy self-sufficiency and to create additional demand for agricultural commodities. The introduction of mandatory blending requirements and lavish subsidies spurred fast adoption of this technology. In the course of 2008, the already existing controversy about the effectiveness of this strategy culminated as the resulting upward shift in demand contributed to staggering rises in food prices on world markets. It is uncertain as yet whether this will tone done current ambitions among policy makers to expand biofuel production. The paper shows that high ratios of energy prices to food prices are needed to make biofuel production profitable without the mandatory blending and subsidies. Yet, even if food-based biofuels disappeared, the issue remains that rising high energy prices will promote intensified use worldwide of land for energy crops, requiring huge amounts of mineral fertilizers and putting nature under additional pressure. In policy terms, this defines three major tasks. The first is replacing the current excise taxes on energy carriers by a uniform carbon tax, so as to mitigate greenhouse gas emissions in an efficient manner, the second to prevent price fluctuations on the oil markets from destabilizing food markets, as happened in recent years. Introduction of upper limits on the use of food for biofuel could prove effective here. The third, much wider, task is to make the transition to a partly biomass based energy production possible and sustainable, that is establishing fair distribution of property and user rights over the lands, while safeguarding biodiversity and soil fertility and maintaining adequate labour standards and living conditions, also during periods that these become non-profitable following a drop in energy prices. The authors thank Lia van Wesenbeeck for her comments.     

THE DEMAND FOR BEVERAGES AND INTERBEVERAGE SUBSTITUTION IN THE UNITED STATES

The analysis in this paper is directed at measuring the substitution between seven beverages consumed in the United States with the objective of shedding some light on just what is the relevant market for antitrust purposes. With regard to the overall beverage market considerations, there is a clear indication that consumers do substitute between different types of beverages. What must be subjectively resolved, however, is whether the extent of the indicated substitution is of significant enough magnitude to infer that two different beverages are in the same product market.