Hari K. Rajagopalan

A multiperiod set covering location model for dynamic redeployment of ambulances

Emergency medical service (EMS) providers continually seek ways to improve system performance particularly the response time to incidents. The demand for ambulances fluctuate throughout the week, depending on the day of week, and even the time of day, therefore EMS operators can improve system performance by dynamic relocation/redeployment of ambulances in response to fluctuating demand patters. The objective of the model is to determine the minimum number of ambulances and their locations for each time cluster in which significant changes in demand pattern occur while meeting coverage requirement with a predetermined reliability. The model is further enhanced by calculating ambulance specific busy probabilities and validated by a comprehensive simulation model. Computational results on experimental data sets and data from an EMS agency are provided.

Application of complex adaptive systems to pricing of reproducible information goods

Piracy of copyrighted information goods such as computer software, music recordings, and movies has received increased attention in the literature. Much of this research relied on mathematical modeling to analyze pricing policies, protection against piracy, and government policies. We use complex adaptive systems as an alternative methodology to analyze pricing decisions in an industry with products which can be pirated. This approach has been previously applied to pricing and can capture some aspects of the problem which are difficult to analyze using traditional mathematical modeling. The results indicate that advances in technology make a skimming strategy the least preferable approach for producers. Further, improvements in technology, more specifically data communications and the Internet, will erode the profitability of a skimming strategy. The analysis also indicates that complex adaptive systems may provide a useful method for analyzing problems in which interactions between participants in the systems, i.e. consumers, sellers, and regulating agencies, are important in determining the behavior of the system.

Can piracy lead to higher prices in the music and motion picture industries

Piracy of copyrighted goods has received increased attention in the literature. Much of this research has focused on pricing policies, protection against piracy, and governmental policies in the software industries. In this paper, we focus on pricing policies of producers in the music and motion picture industries. Exact analytical results are difficult to obtain; therefore, we develop an approximating function of the cumulative demand. This enables us to obtain closed-form expressions for the optimal price. Our results show that the existence of piracy in these industries and the lack of positive network externalities may cause monopolists to charge higher prices to optimize profits. These prices increase with increases in the speed of piracy and longer product lifecycles. We demonstrate the accuracy of our demand approximation function using a numerical experiment. We show how a two-price strategy and dual distribution channels may help in reducing the negative effects of piracy. We perform some numerical sensitivity analysis and provide managerial insights.

Analysis of the effectiveness of manufacturer-sponsored retailer gift cards in supply chains

Some manufacturers sponsor “free” retailer gift cards to be given to consumers who purchase their products. These gift cards are paid for by the manufacturer and are redeemable on all products at the retailer. We develop a model of such a supply chain. We analyze cases in which the gift cards’ redemption rate is constant or increasing in gift card value. The results indicate that in addition to the redemption rate and consumers’ valuation for gift card dollars, the profitability of manufacturer-sponsored gift cards depends on the average gross margin of the retailer and the type of purchases consumers make with gift cards. Furthermore, we show that under certain conditions, free gift cards will increase the expected profits of the retailer and manufacturer as well as decrease the retail price of the product. These conditions include a retailer with large average gross margin and consumers using gift cards to purchase products they would not buy with cash otherwise. Furthermore, all consumers, including those who do not redeem the gift card, are more likely to benefit from a reduced retail price when their probability of redeeming the gift card after purchase is equal to their estimated redemption probability at purchase time. We show the conditions under which gift cards are more profitable than cash mail-in rebates. We develop an incentive scheme to improve the performance of supply chains with gift cards.

The dynamic redeployment coverage location model

Demand for ambulances is known to fluctuate spatially and temporally by day of the week and time of day. Faced with fluctuating demand during the day, emergency medical systems (EMS) managers utilize redeployment strategies to meet demand. Such shifting of personnel, although better able to cover a region with fluctuating demand, can cause fatigue amongst ambulance crew members. Considering these phenomena, we extend the dynamic available coverage location model to be driven by two objectives: (1) Minimize the number of ambulances, and (2) Minimize the number of redeployments for a given fleet during a given shift. We develop a heuristic search algorithm and present the comparative statistics using real data from an urban EMS agency. Our findings suggest that EMS managers can effectively balance a need for additional ambulances with those redeployments required to meet variable demand patterns.

The Value of Information Systems to Small and Medium-Sized Enterprises: Information and Communications Technologies as Signal and Symbol of Legitimacy and Competitiveness

Small and medium-sized enterprises (SMEs) face more serious challenges to their survival than do larger firms. To succeed, SMEs must establish and maintain credibility in the marketplace to attract the resources required for survival. Most co-opt legitimacy by mimicking the cues that signal credibility to convince potential stakeholders that something stands behind their promises. This research examines the role of information and communications technology (ICT) in legitimacy-building from the perspective of both SME founders and customers. In-depth, semi-structured interviews were conducted in a variety of industries to determine whether the ICT-related legitimacy schema from the customers’ perspective differs substantially from that of firm founders. Results indicate that customers compare the ICT information provided in SME’s sales pitches to pre-existing ICT expectations about the nature of desirable sales transactions. We describe the relationship between violations of ICT expectations, legitimacy, and purchase decisions. Implications for theory and practice are discussed.

Reducing disparities in large-scale emergency medical service systems

Emergency Medical Service (EMS) systems operate under the pressure of knowing that human lives might be directly at stake. In the public eye there is a natural expectation of efficient response. There is abundant literature on the topic of efficient planning of EMS systems (maximizing expected coverage or minimizing response time). Other objectives have been considered but the literature available is very sparse compared to efficiency-based works. Furthermore, while real size EMS systems have been studied, the use of exact models is usually hindered by the amount of computational time required to obtain solutions. We approach the planning of large-scale EMS systems including fairness considerations using a Tabu Search-based heuristic with an embedded approximation procedure for the queuing submodel. This allows for the analysis of large-scale real systems, extending the approach in which strategic decisions (location) and operative decisions (dispatching) are combined to balance efficiency and fairness.

Decision Making for Emergency Medical Services

When a medical emergency is recognized, citizens of communities across the USA call 9-1-1. As taxpayers, citizens assume that their local Emergency Medical Services (EMS) agency is always ready to respond quickly and provide necessary treatments to save lives, alleviate pain and suffering, or otherwise address citizens’ concerns. Designing and operating EMS emergency response systems is a major area of research which directly affects communities. One of the primary goals of this research is to provide EMS administrators with viable ambulance location models for improving response times. The first step toward improving response times is to improve forecasting methods. Accurate forecasting provides EMS administrators with pertinent information about when and where calls for ambulances are likely to originate. Given this information EMS administrators can then attempt to locate their ambulances to maximize coverage over a given geographical area. However, calls for ambulances vary both temporally and spatially, forcing EMS administrators to frequently relocate their ambulances as demand patterns change. Forecasting the changes in these demand patterns, as well as determining the different locations ambulances need to be placed at different times of the day, is an important aspect in the successful day-to-day operations for any EMS administrator. However, frequent relocations cause fatigue and loss of morale among ambulance personnel. Our research enables EMS administrators to address these concerns while delivering highest-quality service with limited resources.