Pricing in a duopoly with a lead time advantage

We analyze the price competition between two suppliers offering two different lead times and two different prices to a buyer. The buyer chooses its inventory replenishment policy in order to minimize its infinite-horizon average cost. In essence, the fast and expensive supplier is used only in emergencies, while the slow and cheap supplier receives the bulk of the orders. Thus, despite a higher price, the fast supplier is able to capture a part of the buyer's orders. We analyze the price competition between the asymmetric suppliers, where the market share of each supplier is derived from the buyer's inventory problem. We find equilibria that differ significantly from the Bertrand price-only competition. In particular, for some cost parameters, the fast supplier is able to charge a premium for faster delivery, and stay in business even with a higher production cost. We obtain in some cases closed-form formulas for the price difference in equilibrium. Hence, our results show that high cost suppliers may not be driven out of business if they can offer fast delivery.offshoring; dual sourcing;

Competing for shelf space

This paper studies competition for shelf space in a multi-supplier retail point. We consider a retailer that seeks to allocate her shelf space to maximize her profit. Because products associated with larger profit margin are granted more shelf space, suppliers can offer the retailer financial incentives to obtain larger space allocations. We analyze the competitive dynamics arising from the scarcity of space, and show existence and uniqueness of equilibrium. We then demonstrate that the inefficiencies from decentralizing decision-making are limited to 6% with wholesale-price contracts, and that full coordination can be achieved with pay-to-stay fee contracts. We finally investigate how competition is distorted under the practice of category management.Game theory; Supply chain competition; Price of Anarchy; Pricing; Supply contracts;

Myopic inventory policies using individual customer arrival information

We investigate optimality of myopic policies using the single-unit decomposition approach in inventory management. We derive, under certain conditions, closed-form replenishment decisions, which we call a base-probability policy. That is, the order associated with a given customer is placed if and only if its arrival probability within the lead-time is higher than a threshold.inventory management; base-stock policies; myopic policies;

Competition in the supply option market

This paper develops a multi-attribute competition model for procurement of short life cycle products. In such an environment, the buyer installs dedicated production capacity at the suppliers before the demand is realized. Final production orders are decided after demand materializes. Of course, the buyer is reluctant to bear all the capacity and inventory risk, and thus signs flexible contracts with several suppliers. We model the suppliers' offers as option contracts, where each supplier charges a reservation price per unit of capacity, and an execution price per unit of delivered supply. These two parameters illustrate the trade-off between total price and flexibility of the contract, and are both important to the buyer. We model the interaction between the suppliers and the buyer as a game in which the suppliers are the leaders and the buyer is the follower. Specifically, suppliers compete to provide supply capacity to the buyer and the buyer optimizes its expected profit by selecting one or more suppliers. We characterize the suppliers' equilibria in pure strategies for a class of customer demand distributions. In particular, we show that this type of interaction gives rise to cluster competition. That is, in equilibrium, suppliers tend to be clustered in small groups of two or three suppliers each, such that within the same group all suppliers use similar technologies and offer the same type of contract. Finally, we show that in equilibrium, the supply chain inefficiencies, i.e., the loss of profit due to competition, are in general at most 25% of the profit of a centralized supply chain, for a wide class of demand distributions.supplier portfolio; supplier competition;

Improving supply chain efficiency through wholesale price renegotiation

In a decentralized supply chain, double marginalization is an important source of inefficiency. We suggest in this paper a simple mechanism to reduce it that uses a wholesale price contract and renegotiation. Our mechanism only requires repeated interaction, and rational behavior from the players. Specifically, over T rounds of negotiation, the supplier proposes different prices in each round, and the buyer places orders at the quoted price. Even though prices are decreasing in time, the buyer places a positive order, to force the supplier to reduce its price in the following round. This interaction results in higher profits for both supplier and buyer. We solve the buyer and supplier problems and show that, as T increases, supply chain efficiency tends to 100%, and the sub-optimality gap decreases with 1/T. Finally, we discuss how these results can be applied to design negotiation processes.strategic customer; dynamic pricing; supply chain;

A capacitated commodity trading model with market power

In this paper we consider the problem of a trader who purchases a commodity in one market and resells it in another. The trader is capacitated: the trading volume is limited by operational constraints, e.g., logistics. The two markets quote different prices, but the spread is reduced when trading takes place. We are interested in finding the optimal trading policy across the markets so as to obtain the maximum profit in the long-term, taking into account that the trading activity influences the price processes, i.e., market power. As in the no-market-power case, we find that the optimal policy is determined by three regions, where 1) move as much as possible from one market to the other; 2) the same in the opposite direction; or 3) do nothing. Finally, we use the model to analyze kerosene price differences between New York and Los Angeles.commodity trading; price processes; inventory management;

The Future of Retail Operations

Retailing consists of all the activities associated with the selling of goods to the final consumer. In this article, we review the research on retail operations published in Manufacturing & Service Operations Research (M&SOM) since 1999. We then discuss the current retail landscape and the new research directions it offers, in which M&SOM can play a prominent role

A Note on Shapleys Convex Measure Games

L. S. Shapley, in his paper Cores of Convex Games, introduces Convex Measure Games, those that are induced by a convex function on R, acting over a measure on the coalitions. But in a note he states that if this function is a function of several variables, then convexity for the function does not imply convexity of the game or even superadditivity. We prove that if the function is directionally convex, the game is convex, and conversely, any convex game can be induced by a directionally convex function acting over measures on the coalitions, with as many measures as players.supermodularity, multilinear extension, convex cooperative games, directional convexity

The Candy Project: the re-enchantment of candy in a liquid world

Sugar consumption has become an extremely serious problem, especially since its incorporation into every type of food not only those considered to be sweet culturally. This is not exclusively a health problem but also a gastronomic one, since this “invisible sugar” is perceptible by the stomach but not by the senses. Sugar’s ubiquity has led to its demonization. The consumption of candy has been one of the victims of this process. A social image of “empty calories”, or food without nutrients, has been built up around it. In this article I want to emphasize what this “medicalized” image of candy leaves out: the social, imaginary, nutritional and gastronomic potentialities of this form of alimentation. It is true that since sugar became invisible we have no understanding of its power. But by focusing solely on negative aspects we overlook the potentiality of candy as, amongst other things, vehicles for nutritional socialization and education in taste. Redeeming candy thus involves changing the social imaginaries associated with it. This new imaginary is largely emerging in the field of internet and the new technologies

Assignment markets with the same core

In the framework of bilateral assignment games, we study the set of matrices associated with assignment markets with the same core. We state conditions on matrix entries that ensure that the related assignment games have the same core. We prove that the set of matrices leading to the same core form a join-semilattice with a nite number of minimal elements and a unique maximum. We provide a characterization of the minimal elements. A sucient condition under which the join-semilattice reduces to a lattice is also given.core, semilattice, assignment game