Papers by Apostolos Burnetas
In this paper we study a situation in which a broker must manage the procurement of a short life ... more In this paper we study a situation in which a broker must manage the procurement of a short life cycle product. As the broker observes demand for the item, she learns about the demand process. However, as is often the case in practice, it becomes either more difficult or more expensive to procure the item as the selling season advances. Thus, the broker must trade-off higher procurement costs against the benefit of making ordering decisions with better information about demand. Problems of this type arise, for example, in the travel industry, where a travel agent's cost of procuring airline and hotel reservations increases as the date of a vacation package approaches. We develop a newsvendor-like characterization of the optimal procurement policy. In a numerical analysis, we demonstrate how broker procurements tend to cluster just before price increases and how brokers can benefit from explicitly considering the effects of information about demand in their ordering policies.
A Review of:“Introductory Statistics” Sheldon Ross McGraw Hill, 1996
If you remember the classic non-spreadsheet version all examples in the text are included. I reco... more If you remember the classic non-spreadsheet version all examples in the text are included. I recommend of the text, the revision is a good improvement. Not this book for those of you interested in providing a only are there a few more cases, but consider the CD‘desktop’ application focus to your master’s degree ROM that comes with the text. A student version of students. Crystal Ball, Treeplan, GLP, EXCEL templates for queuing models, voice-annotated ‘tutorials’ on the use Reviewed by Rick L. Wilson, Oklahoma State University, of EXCEL add-ins, and EXCEL spreadsheet files for USA
Springer Optimization and Its Applications, 2012
We consider the problem of sequential sampling from a finite number of independent statistical po... more We consider the problem of sequential sampling from a finite number of independent statistical populations to maximize the expected infinite horizon average outcome per period, under a constraint that the expected average sampling cost does not exceed an upper bound. The outcome distributions are not known. We construct a class of consistent adaptive policies, under which the average outcome converges with probability 1 to the true value under complete information for all distributions with finite means. We also compare the rate of convergence for various policies in this class using simulation.
We develop asymptotically optimal policies for the multi armed bandit (MAB), problem, under a cos... more We develop asymptotically optimal policies for the multi armed bandit (MAB), problem, under a cost constraint. This model is applicable in situations where each sample (or activation) from a population (bandit) incurs a known bandit dependent cost. Successive samples from each population are iid random variables with unknown distribution. The objective is to have a feasible policy for deciding from which population to sample from, so as to maximize the expected sum of outcomes of n total samples or equivalently to minimize the regret due to lack on information of sample distributions, For this problem we consider the class of feasible uniformly fast (f-UF) convergent policies, that satisfy sample path wise the cost constraint. We first establish a necessary asymptotic lower bound for the rate of increase of the regret function of f-UF policies. Then we construct a class of f-UF policies and provide conditions under which they are asymptotically optimal within the class of f-UF policies, achieving this asymptotic lower bound. At the end we provide the explicit form of such policies for the case in which the unknown distributions are Normal with unknown means and known variances.
Evolution-based Optimization Models of Complex Interacting Systems
this paper is based on that of the NK model of Kauman & Levin (1987), and Kauman (1993), develope... more this paper is based on that of the NK model of Kauman & Levin (1987), and Kauman (1993), developed for studying the biological evolution of chromosomes. Using their approach in our context, each component chosen for part i contributes an amount, p i (x), to the overall performance of the system x. The performance, p(x), of the whole system x is then taken to be the average of these individual performance contributions:
Nonlinear pricing in single period supply contracts with asymmetric demand information
On power one estimation from simulation of finite Markov chains
Asymptotically Efficient Adaptive Policies for Markovian Decision Processes
Quantity Discounts in Single Period Supply
We investigate how a quantity discount schedule can be used to influence stocking decisions and s... more We investigate how a quantity discount schedule can be used to influence stocking decisions and supply chain performance in single-period interactions between a supplier and buyer(s). In contrast to much of the work that has been done on single-period supply contracts, we assume that there are no interactions between the supplier and the buyer(s) after demand information is revealed. Furthermore, we assume that there are either heterogeneous buyers or that there is a single buyer that has better information about the distribution of demand than does the supplier. We derive structural properties of this unique problem that facilitate managerial insights and solution procedures.
Efficient estimation and control for Markov processes
Proceedings of 1995 34th IEEE Conference on Decision and Control, 1995
ABSTRACT Considers the problem of sequential control for a finite state and action Markovian deci... more ABSTRACT Considers the problem of sequential control for a finite state and action Markovian decision process with incomplete information regarding the transition probabilities P∈P˜. Under suitable irreducibility assumptions for P˜, the authors construct adaptive policies that maximize the rate of convergence of realized rewards to that of the optimal (non adaptive) policy under complete information. These adaptive policies are specified via an easily computable index function, of states, controls and statistics, so that one takes a control with the largest index value in the current state in every period
Supply chain coordination under discrete information asymmetries and quantity discounts
Omega, 2015
ABSTRACT We consider a two node supply chain with a rational manufacturer-retailer pair, in which... more ABSTRACT We consider a two node supply chain with a rational manufacturer-retailer pair, in which the retailer has private information that affects the nodes' reservation levels. Quantity discounts offered by the manufacturer is the mechanism we propose in order to achieve reduced costs for both supply chain nodes. We derive analytical expressions of the quantity discounts that minimize the manufacturer's costs, while enabling the establishment of the business. Furthermore, we show that perfect coordination is possible even under asymmetric information. Sensitivity analysis and numerical examples offer evidence of the robustness of the results and of the potential of the approach for applications to real-life business ventures.
Non-Linear Pricing in Single Period Supply Contracts with Asymmetric Demand Information
Applied Optimization, 2002
Partial Quick Response Policies in a Supply Chain
Applied Optimization, 2005
ABSTRACT It has been well documented that buyers can benefit significantly from being able to pla... more ABSTRACT It has been well documented that buyers can benefit significantly from being able to place reactive orders in response to observed demand for a short life cycle product. In practice, suppliers often fill these reactive orders with less than total reliability. Although reactive order fulfillment can allow the supply chain to capture more of the demand that is realized, it can also deter retailers from ordering as much initially. In this chapter, we investigate how this trade-off affects the retailers’ ordering behavior as well as the profits of the manufacturer, the retailers, and the supply chain as a whole. We also develop insight as to how a manufacturer should offer a reactive ordering policy.
Effects of different priority policies on the capacity design for multiclass queues
The editors wish to gratefully acknowledge all referees who have generously given their time to provide valuable assistance in maintaining the quality of OR Spectrum. The following referees have contributed during the time of origin of volume 31
Queueing Systems, 2007
We consider a single server Markovian queue with setup times. Whenever this system becomes empty,... more We consider a single server Markovian queue with setup times. Whenever this system becomes empty, the server is turned off. Whenever a customer arrives to an empty system, the server begins an exponential setup time to start service again. We assume that arriving customers decide whether to enter the system or balk based on a natural reward-cost structure, which incorporates their desire for service as well as their unwillingness to wait.
The effect of discounts on optimal pricing under limited capacity
International Journal of Operational Research, 2011
ABSTRACT This paper considers the problem of optimal pricing in a system serving two classes of c... more ABSTRACT This paper considers the problem of optimal pricing in a system serving two classes of customers differentiated by their delay sensitivities. We derive the revenue maximising pricing policies whether or not price discrimination is an option. We find that in both cases the optimal policy causes the less delay-sensitive class to enter first, and the optimal prices are increasing in capacity under price discrimination, which is not generally true when price discrimination is not allowed. Furthermore, under price discrimination, less capacity is needed to capture a customer class or the entire market, while, more customers are served and higher revenue is generated. Finally, we use an M/M/1 system to provide further insights and numerical analysis.
Pricing and capacity allocation under asymmetric information using Paris Metro Pricing
International Journal of Operational Research, 2009
ABSTRACT We consider a Paris Metro Pricing (PMP) approach for providing service to two classes of... more ABSTRACT We consider a Paris Metro Pricing (PMP) approach for providing service to two classes of customers differentiated by their delay sensitivity. We develop a leader-follower game, where the leader is the service provider who sets the price and the customers respond by deciding whether to join or balk. We derive the customer behaviour as the Nash equilibrium of a multi-person game and obtain the revenue maximising price pairs for all combinations of arrival rates from each class to each server. We finally derive the capacity threshold in such domain and its impact on customer accessibility to the product or service.
The Inventory Routing Problem
Fleet Management and Logistics, 1998
Abstract Vendor managed resupply is an emerging trend in logistics and refers to situ-ations in w... more Abstract Vendor managed resupply is an emerging trend in logistics and refers to situ-ations in which a supplier manages the inventory replenishment of its customers. Vendors save on distribution cost by being able to better coordinate deliveries to different customers, and ...
Uploads
Papers by Apostolos Burnetas