Operations & Supply Chain Management

We develop a competitive pricing model which combines the complexity of time-varying demand and cost functions and that of scale economies arising from dynamic lot sizing costs. Each firm can replenish inventory in each of the T periods into which the planning horizon is partitioned. Fixed as well as variable procurement costs are incurred for each procurement order, along with inventory carrying costs. Each firm adopts, at the beginning of the planning horizon, a (single) price to be employed throughout the horizon.

Generalizing earlier work on staffing and routing in telephone call centers, we consider a processing network model with large server pools and doubly stochastic input flows. In this model the processing of a job may involve several distinct operations. Alternative processing modes are also allowed. Given a finite planning horizon, attention is focused on the two-level problem of capacity choice and dynamic system control. A pointwise stationary fluid model (PSFM) is used to approximate system dynamics, which allows development of practical policies with a manageable computational burden.

We study the product design problem of a revenue-maximizing firm that serves a market where customers are heterogeneous with respect to their valuations and desire for a quality attribute and are characterized by a perhaps novel model of customer choice behavior. Specifically, instead of optimizing the net utility that results from an appropriate combination of prices and quality levels, customers are "satisficers" in that they seek to buy the cheapest product with quality above a certain customer-specific threshold.

Many new products (e.g., PDA phones) share features with multiple categories, but are also significantly different from each of these categories. When consumers encounter such a product, they may create a new subcategory (e.g., smart phones) to accommodate it. In such situations, consumers must decide where to position the new subcategory. We develop the Category Activation Model (CAM) to predict where within a category structure consumers are likely to position a subcategory that they have created to accommodate a new product that could potentially belong to multiple product categories.

Traditional monopoly pricing models assume that firms have full information about the market demand and consumer preferences. In this article, we study a prototypical monopoly pricing problem for a seller with limited market information and different levels of demand learning capability under relative performance criterion of the competitive ratio (CR). We provide closed-form solutions for the optimal pricing policies for each case and highlight several important structural insights.

We consider the one-armed bandit problem of Woodroofe [J. Amer. Statist. Assoc. 74 (1979) 799–806], which involves sequential sampling from two populations: one whose characteristics are known, and one which depends on an unknown parameter and incorporates a covariate. The goal is to maximize cumulative expected reward. We study this problem in a minimax setting, and develop rate-optimal polices that involve suitable modifications of the myopic rule.

As the diversity in end-user devices and networks grows, it becomes important to be able to efficiently and adaptively serve media content to different types of users. A key question surrounding adaptive media is how to do Rate-Distortion optimized scheduling. Typically, distortion is measured with a single distortion measure, such as the Mean-Squared Error compared to the original high resolution image or video sequence.

In many industries, firms consider the option of outsourcing an important service process associated with the goods or services they bring to the market. Often, competing firms outsource this service process to one or more common service suppliers. When they outsource to a common service provider, this gives rise to a service supply chain.

We describe research on a supply chain contracting problem that was sponsored by a major semi-conductor manufacturer. The manufacturer sells products (semi-conductor parts) with varying quality levels through a network of distributors to end consumers (independent computer shops, system configurators, hobbyists, etc.) who have heterogeneous valuations for quality. Since production costs for semi-conductors are essentially independent of quality levels (within a part family), the manufacturer earns much more selling higher quality parts.