Soulaymane Kachani

Columbia University | CU · Department of Industrial Engineering and Operations Research

We study the dynamic bilateral price negotiations from the perspective of a monopolist seller. We first study the classical static problem with an added uncertainty feature. Next, we review the dynamic negotiation problem, and propose a simple deterministic “fluid” analog. The main emphasis of the paper is in analyzing the relationship of the dynam...

This paper addresses the problem of pricing for an airline or a retailer selling one product to a stream of repeated customers over an infinite time horizon. We propose a dynamic pricing model that incorporates the concept of customers' reference price. We derive an optimal pricing policy and prove its monotone convergence in a monopoly context. We...

This paper presents a reference price model for competition in a duopoly market for a single product. We derive Markov-Perfect equi-librium pricing policies. We provide a closed-form heuristic and demon-strate that it is very close to the equilibrium. We also derive closed-form solutions for pricing policies of a retailer who is an optimizer when i...

This study investigates the relationship between operational efficiency and stock performance. The analysis is conducted by building an efficiency-based stock selection strategy and assessing its performance over different investment horizons in a contextual and empirical setting provided by the U.S. Information Technology sector. By means of data...

We consider the problem where a number of firms simultaneously compete in price and inventory level decisions. Each firm offers a line of several products, both complementary products and substitutes, the product line demand is also sensitive to prices of outside competitors' products. We also consider the case of excess demand, where the firm face...

In this article, we explore the current-state of literature on how dynamic pricing models incorporate consumer reference-price effects in developing more informed dynamic pricing strategies for products that have repeated consumer interactions. We first examine the literature on how consumer demand is impacted by reference-price effects and how con...

We address the problem of simultaneous pricing of a line of several products, both complementary products and substitutes, with a number of distinct price differentiation classes for each product (e.g., volume discounts, different distribution channels, and customer segments) in both monopolistic and oligopolistic settings. We provide a generic fra...

In this article, we consider the revenue management problem of firms with customers who use historical pricing data to make their purchasing decision. This behavior is modeled using the concept of reference price, which quantifies customers’ perceived ‘fair value’ of a product. We consider a segmented market consisting of two types of customers. On...

In this paper, we address the problem of a magazine publishing firm facing stochastic demand over multiple periods. We model the dynamics of customer subscription and retention/attrition. We identify the key decision variables to enhance magazine profitability: production quantity, subscription price, and newsstand price. First, we provide a dynami...

In this paper we introduce travel time models that incorporate spillback and bottleneck phenomena. In particular, we study a model for determining the link travel times for drivers entering a link as well as drivers already in the link but whose travel times are affected by a significant change in traffic conditions (e.g. spillback or bottleneck ph...

We consider a firm's timing of new product introductions and pricing of multiple product generations. We analyse the case where a firm manages multiple generations of a product, and where demand of each generation is impacted by the prices of all existing generations and the introduction of new generations. In the case of two successive product gen...

Over the past decade, revenue management techniques have been extensively developed in the airline and hotel industries. Much of the research has been on the optimisation front, which focuses on finding the optimal seat allocation policy to maximise revenue. There has been, however, less published work on forecasting issues. In this paper, we prese...

This paper focuses on joint dynamic pricing and demand learning in an oligopolistic market. Each firm seeks to learn the price-demand relationship for itself and its competitors, and to set optimal prices, taking into account its competitors’ likely moves. We follow a closed-loop approach to capture the transient aspect of the problem, that is, pri...

Fluid dynamics models provide a powerful deterministic technique to approximate stochasticity in a variety of application areas. In this paper, we study two classes of fluid models, investigate their relationship as well as some of their applications. This analysis allows us to provide analytical models of travel times as they arise in dynamically...

The anticipatory route guidance problem (ARG), an extension of the dynamic traffic user-equilibrium problem, consists of providing messages, based on forecasts of traffic conditions, to assist drivers in their path choice decisions. Guidance becomes inconsistent when the forecasts on which it is based are in-validated by drivers' reactions to the p...

We study the pure capital rationing and the horizon capital budgeting problems using a robust optimization framework. The models and the methodology we propose take into account the uncertainty of the input data. The uncertainty of the cash flows is modeled as a range of values that is allowed for each uncertain data. Unlike stochastic models, this...

In this paper, we introduce a fluid model of dynamic pricing and inventory management for make-to-stock manufacturing systems. Instead of considering a traditional model that is based on how price affects demand, we consider a model that relies on how price and level of inventory affect the time a unit of product remains in inventory. Our motivatio...

In this paper, we take a fluid dynamics approach to determine the travel time in traversing a network's link. We propose a general model for travel time functions that utilizes fluid dynamics laws for compressible flow to capture a variety of flow patterns such as the formation and dissipation of queues, drivers' response to upstream congestion or...

In this paper we introduce travel time models that incorporate spillback and bottleneck phenomena. In particular, we study a model for determining the link travel times for drivers entering a link as well as drivers already in the link but whose travel times are affected by a significant change in traffic conditions (e.g. spillback or bottleneck ph...

Fluid dynamics models provide a powerful deterministic technique to approximate stochasticity in a variety of application areas. In this paper, we study two classes of fluid models, investigate their relationship as well as some of their applications. This analysis allows us to provide analytical models of travel times as they arise in dynamically...

This thesis investigates dynamic phenomena that arise in a variety of systems that share similar characteristics. A common characteristic of particular interest in this work is travel time. We wish to address questions of the type: How long does it take a driver to traverse a route in a transportation network? How long does a unit of product remain...

Concerns traffic congestion, especially in intelligent vehicle highway systems (IVHS); addressing such questions as how traffic patterns form and how congestion can be alleviated. Understanding drivers' travel times is key to this problem. We present macroscopic models for determining analytical forms for travel times. We take a fluid dynamics appr...

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2000. Includes bibliographical references (leaves 134-137).