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;

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;

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;

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;

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

Private label introduction: Does it benefit the supply chain?

Private labels, also called store brands or distributor brands, have changed the retail industry during the last three decades. Consumer data shows strong growth of private label market share, and in countries like Germany or Spain, the penetration of private labels is above 30% of total retail sales. This paper analyzes the channel dynamics in a category where a private label is introduced. We focus on the impact of private labels on retail and wholesale equilibrium prices, as well as on the profits of each firm of the supply chain. While private label introduction helps the retailer reduce manufacturer brand's prices, we find that it does not always improve the total profits of the supply chain. Generally, the supply chain benefits from this introduction only when cross-elasticities are small, i.e., competitive interactions are weak. With our model, we formulate the general conditions under which retailers should consider introducing private labels.Private label; non-cooperative game theory; supply chain efficiency;

A characterization of optimal base-stock levels for a continuous-stage serial supply chain

In this paper, we present a continuous model to optimize multi-echelon inventory management decisions under stochastic demand. Observing that in such continuous system it is never optimal to let orders cross, we decompose the general problem into a set of single-unit sub-problems that can be solved in a sequential fashion. When shipping and inventory holding costs are linear in the stage, we show that it is optimal to move the unit associated with the k-th next customer if and only if the inventory unit is held in an echelon located within a given interval. This optimal policy can be interpreted as an echelon base-stock policy such that the base-stock is initially increasing and then decreasing in the stage. We also characterize the optimal policy when costs are piecewise-constant. Finally, we study the sensitivity of the optimal base-stock levels to the cost structures.multi-echelon; optimal control; unit-tracking decomposition;

Optimal expediting decisions in a continuous-stage serial supply chain

In this paper, we analyze expediting decisions in a continuous-time, continuous-stage serial supply chain facing a Poisson demand process. For each unit in the chain, one must decide at which speed it should be moved downstream, given the state of the system, so as to minimize total supply chain costs. We decompose the problem into a set of one-dimensional subproblems that can be easily solved and characterize the optimal expediting policy: under quite general assumptions, the optimal speed of a given unit accelerates upstream, and then slows down downstream. We finally provide a case study where we estimate the benefits of expediting compared to a fixed transportation speed and show them to be significant.lead-time management; optimal control; unit-tracking decomposition;