Empirical Studies In Retail Operations

This dissertation contains three essays. The first essay, entitled \textit{ Does Inventory Increase Sales? The Billboard and Scarcity Effects in U.S. Automobile Dealerships } looks into the relationship between inventory and demand beyond the obvious stockout effect. Inventory might signal a popular, and therefore a desirable, product, thereby increasing sale. Or, inventory might encourage a consumer to continue her search, thereby decreasing sales. In this paper we seek to identify these effects in U.S. automobile sales. Our primary research challenge is the endogenous relationship between inventories and demand. Hence, our estimation strategy relies on weather shocks at upstream production facilities to create exogenous variation in downstream dealership inventory. We find that the impact of adding a vehicle of a particular model to a dealer\u27s lot depends on which cars the dealer already has. If the added vehicle expands the available set of sub-models (e.g., adding a four-door among a set that is exclusively two-door), then sales increase. But if the added vehicle is of the same sub-model as an existing vehicle, then sales actually decrease. Based on this insight, given a fixed set of cars, they should be allocated among a group of dealers so as to maximize each dealer\u27s variety. The second essay, entitled \textit{ Severe Weather and Automobile Assembly Productivity }, is related to the first one in that presents a detail analysis of the exogenous shock presented there: The weather impact on vehicles assembly lines. It is apparent that severe weather should hamper the productivity of work that occurs outside. But what is the effect of extreme rain, snow, heat and wind on work that occurs indoors, such as the production of automobiles? Using weekly production data from 64 automobile plants in the United States over a ten-year period, we find that adverse weather conditions lead to a significant reduction in production. Across our sample of plants, severe weather reduces production on average by 1.5\%. While it is possible that plants are able to recover these losses at some later date, we do not find evidence that recovery occurs in the week after the event. Our findings are useful both for assessing the potential productivity shock associated with inclement weather as well as guiding managers on where to locate a new production facility. The third essay, entitled \textit{ Integration of Online and Offline Channels in Retail: The Impact of Sharing Reliable Inventory Availability Information }. In this essay we focus the attention on the impact of inventory information disclosure. Increasingly, retailers are integrating their offline and online channels to reduce costs or to improve the value proposition they make to their customers. Using a proprietary dataset, we analyze the impact of the implementation of a buy-online-pickup-in-store project. Contrary to our expectations, the implementation of this project is associated with a reduction in online sales and an increase in store sales and traffic. We interpret the results in light of recent operations management literature that analyzes the impact of sharing inventory availability information online. The implementation of a buy-online-pickup-in-store project provides an exogenous shock to the verifiability of the inventory information that the firm shows to their customers. Our analysis illustrates the challenges of drawing conclusions about complex interventions using single channel data

Integration of Online and Offline Channels in Retail: The Impact of Sharing Reliable Inventory Availability Information

Using a proprietary data set, we analyze the impact of the implementation of a “buy-online, pick-up-in-store” (BOPS) project. The implementation of this project is associated with a reduction in online sales and an increase in store sales and traffic. These results can be explained by two simultaneous phenomena: (1) additional store sales from customers who use the BOPS functionality and buy additional products in the stores (cross-selling effect) and (2) the shift of some customers from the online to the brick-and-mortar channel and the conversion of noncustomers into store customers (channel-shift effect). We explain these channel-shift patterns as an increase in “research online, purchase offline” behavior enabled by BOPS implementation, and we validate this explanation with evidence from the change of cart abandonment and conversion rates of the brick-and-mortar and online channels. We interpret these results in light of recent operations management literature that analyzes the impact of sharing inventory availability information. Our analysis illustrates the limitations of drawing conclusions about complex interventions using single-channel data

Does Adding Inventory Increase Sales? Evidence of a Scarcity Effect in U.S. Automobile Dealerships

What is the relationship between inventory and sales? Clearly, inventory could increase sales: expanding inventory creates more choice (options, colors, etc.) and might signal a popular/desirable product. Or, inventory might encourage a consumer to continue her search (e.g., on the theory that she can return if nothing better is found), thereby decreasing sales (a scarcity effect). We seek to identify these effects in U.S. automobile sales. Our primary research challenge is the endogenous relationship between inventory and sales — e.g., dealers influence their inventory in anticipation of demand. Hence, our estimation strategy relies on weather shocks at upstream production facilities to create exogenous variation in downstream dealership inventory. We find that the impact of adding a vehicle of a particular model to a dealer’s lot depends on which cars the dealer already has. If the added vehicle expands the available set of sub-models (e.g., adding a four-door among a set that is exclusively two-door), then sales increase. But if the added vehicle is of the same sub-model as an existing vehicle, then sales actually decrease. Hence, expanding variety across sub-models should be the first priority when adding inventory—adding inventory within a sub-model is actually detrimental. In fact, given how vehicles were allocated to dealerships in practice, we find that adding inventory actually lowered sales. However, our data indicate that there could be a substantial benefit from the implementation of a “maximizes variety, minimize duplication” allocation strategy: sales increase by 4.4 percent without changing the number of vehicles at each dealership, and a 5.2 percent is possible if inventory is allowed to decrease by 2.8 percent (and no more than 10 percent at any one dealer)

THE FINITE ELEMENTS METHOD APPLIED TO ELECTROMAGNETIC COMPATIBILITY STUDY

ABSTRAC

Order-Based Trade Credit and Operational Performance in the Nanostore Retail Channel

Millions of nanostores serve bottom-of-the-pyramid consumers in emerging markets. Their suppliers, Consumer Packaged Goods (CPG) companies, struggle with high operational costs that largely stem from shopkeepers’ liquidity constraints. We empirically investigate whether suppliers can improve operational performance by allowing nanostore shopkeepers to delay order payment by a short period of time. We term this delayed payment alternative "Order-Based Trade Credit" (OBTC) and examine the key trade-off suppliers face when transacting with it. OBTC can create efficiency gains in selling and delivering products to nanostores. However, OBTC is risky, as shopkeepers might default on their credit lines. Leveraging data from a nanostore supplier offering OBTC, we assess the effect of this novel policy on the operational performance of the supplier through a difference-in-differences approach. We find that OBTC leads to substantial gains for nanostore suppliers, across a range of important operational drivers. In addition, we show when the benefits of OBTC compensate the risk suppliers take in providing it

Order-Based Trade Credit and Operational Performance in the Nanostore Retail Channel

Millions of nanostores serve bottom-of-the-pyramid consumers in emerging markets. Their suppliers, Consumer Packaged Goods (CPG) companies, struggle with high operational costs that largely stem from shopkeepers’ liquidity constraints. We empirically investigate whether suppliers can improve operational performance by allowing nanostore shopkeepers to delay order payment by a short period of time. We term this delayed payment alternative "Order-Based Trade Credit" (OBTC) and examine the key trade-off suppliers face when transacting with it. OBTC can create efficiency gains in selling and delivering products to nanostores. However, OBTC is risky, as shopkeepers might default on their credit lines. Leveraging data from a nanostore supplier offering OBTC, we assess the effect of this novel policy on the operational performance of the supplier through a difference-in-differences approach. We find that OBTC leads to substantial gains for nanostore suppliers, across a range of important operational drivers. In addition, we show when the benefits of OBTC compensate the risk suppliers take in providing it

Does adding inventory increase sales? Evidence of a scarcity effect in U.S. Automobile dealerships

Copyright: © 2018 INFORMSWhat is the relationship between inventory and sales? Clearly, inventory could increase sales: expanding inventory creates more choice (options, colors, etc.) and might signal a popular/desirable product. Or, inventory might encourage a consumer to continue her search (e.g., on the theory that she can return if nothing better is found), thereby decreasing sales (a scarcity effect). We seek to identify these effects in U.S. automobile sales. Our primary research challenge is the endogenous relationship between inventory and sales-e.g., dealers influence their inventory in anticipation of demand. Hence, our estimation strategy relies on weather shocks at upstream production facilities to create exogenous variation in downstream dealership inventory. We find that the impact of adding a vehicle of a particular model to a dealer's lot depends on which cars the dealer already has. If the added vehicle expands the available set of submodels (e.g., adding a four-door among a set that is exclusively two-door), then sales increase. But if the added vehicle is of the same submodel as an existing vehicle, then sales actually decrease. Hence, expanding variety across submodels should be the first priority when adding inventory-adding inventory within a submodel is actually detrimental. In fact, given how vehicles were allocated to dealerships in practice, we find that adding inventory actually lowered sales. However, our data indicate that there could be a substantial benefit from the implementation of a “maximize variety, minimize duplication” allocation strategy: sales increase by 4.4% without changing the total number of vehicles at each dealership

Planificación de una red GSM/GPRS/UMTS en la ciudad de Guayaquil

Se describe la situación actual de la telefonía móvil en nuestro país y se analiza su evolución poniendo especial énfasis en el ámbito tecnológico. A partir de esta evaluación se analiza la factibilidad de la implementación de una red de 3G en el país. El proyecto propone representar y analizar el camino evolutivo de una red de telefonía móvil cuya meta es brindar servicios de tercera generación en nuestro medio. Trata de abarcar los principales conceptos y dar los fundamentos teóricos al proyecto, enmarcando las tecnologías empleadas. Se describe la herramienta informática que hemos utilizado para realizar ciertas predicciones de tipo radioeléctrico como cobertura y pérdidas de propagación. Además nos referimos a algunas herramientas especializadas en la planificación de sistemas celulares.GuayaquilIngeniero en Electrónica y Telecomunicacione

Indagine conoscitiva sulla violenza verso il maschile

Riassunto La violenza di genere costituisce una tipologia di reato in costante espansione e di continuo interesse da parte della comunità scientifica. Il fenomeno nella sua globalità è complesso da analizzare in quanto gli autori di reato commettono gli episodi perlopiù entro le mura domestiche e ciò comporta, dato il legame spesso di natura intrafamiliare tra autore e vittima, il silenzio di quest’ultima che concorre ad accrescere il cosiddetto “numero oscuro”. Da ciò derivano i limiti dell’analisi di un fenomeno per sua natura sommerso, del quale non è facile tracciare i contorni. Una conoscenza approfondita del fenomeno nel suo insieme, tuttavia, è essenziale per lo sviluppo delle politiche e dei servizi, a partire dalle campagne di sensibilizzazione per arrivare alle contromisure legislative finalizzate a prevenire e/o contenere la violenza. Va rilevato come inchieste, sondaggi e ricerche che analizzano tale comportamento deviante e che vengono proposte con continuità a livello istituzionale e mediatico da diversi decenni, sono solite prendere in considerazione solo l’eventualità che la vittima della violenza di genere sia donna e che l’autore di reato sia uomo. Tale informazione, distorta alla sua origine, passa tramite canali ufficiali (dai media alle campagne di prevenzione) determinando una conseguente sensibilizzazione unidirezionale che relega ad eccezioni - spesso non prese neppure in considerazione - le ipotesi che la violenza possa essere subita e/o agita da appartenenti ad entrambi i sessi. L’indagine presentata in questo articolo è finalizzata a raccogliere elementi di valutazione ancora inesistenti nel nostro Paese, utili a verificare se esista, ed eventualmente in che misura, una realtà diversa da quella fondata esclusivamente su condizionamenti, luoghi comuni e pregiudizi. La violence de genre constitue l’un des crimes qui connaît une forte croissance et qui fait l’objet d’un intérêt certain pour la communauté scientifique. Le phénomène est complexe à analyser dans sa globalité car la plupart des auteurs commettent leurs crimes dans le foyer domestique. Étant donné le lien intrafamilial existant entre l’auteur et la victime, cette dernière reste dans le silence qui contribue à faire augmenter le « chiffre noir ». Par conséquent, l’analyse de ce phénomène, caché à cause de sa propre nature, montre ses limites. Des campagnes de sensibilisation à l’adoption de mesures législatives pour la prévention et répression de la violence, une connaissance approfondie de ce phénomène dans sa globalité est toutefois primordial pour le développement des politiques et des services d’aide aux victimes. Il faut souligner que les enquêtes et les recherches analysant ce comportement déviant et, depuis plusieurs décennies, proposées en permanence à des niveaux institutionnel et médiatique, ont tendance à considérer que la victime de la violence de genre ne peut être qu’une femme et que son auteur, un homme. Cette information, altérée dès le début, passe à travers des chaînes officielles (des médias aux campagnes de prévention) provoquant une sensibilisation unidirectionnelle qui relègue à l’état d’exceptions – qui souvent ne sont même pas prises en considération – les hypothèses que la violence puisse être subie et/ou perpêtrée aussi bien par les hommes que par les femmes. L’enquête présentée dans cet article a pour objectif de collecter des éléments d’évaluation encore inexistants en Italie. Ces données peuvent être utilisées pour vérifier s’il existe une réalité différente de celle qui n’est basée que sur les lieux communs et sur les préjudices et quelle serait sa dimension. Gender-based violence is a constantly increasing crime and continuously attracting a lot of interest in the scientific community. This is a complex phenomenon to analyse as a whole because perpetrators usually commit the acts of violence at home. For this reason, and also due to the intimate relationship between the author and the victim, this latter remains silent, so the dark number increases. Consequently, the analysis of this phenomenon, hidden just because of its nature, has its limits. A deep knowledge of this phenomenon as a whole, however, is important for the development of policies and services, for example sensibilisation campaigns and countermeasures to prevent and combat violence. It is important to point out that surveys and researches studying this deviant behaviour, and continuously proposed at an institutional level and disseminated by mass media, usually consider that the victim of gender-based violence is a woman and the perpetrator a man. This distorted information is transmitted through official channels (for example, mass media and sensibilisation campaigns) producing a consequent unidirectional sensibilisation which relegates as exceptions – often not taken into consideration – hypothesis that violence may be endured and/or committed by both sexes. The purpose of the survey presented in this article is to collect some evaluation data that do not exist yet in our country, data that will be useful in order to verify if it exists in reality, and if yes what extension it has, different from the one based exclusively on common sense and prejudices

Geochemical behavior of an acid drainage system: the case of the Amarillo River, Famatina (La Rioja, Argentina)

The Amarillo River (Famatina range, Argentina, ~29° S and ~67° W) is unusual because acid mine drainage (AMD) is superimposed on the previously existing acid rock drainage (ARD) scenario, as a Holocene paleolake sedimentary sequence shows. In a markedly oxidizing environment, its water is currently ferrous and of the sulfate-magnesium type with high electrical conductivity (>10 mS cm−1 in uppermost catchments). At the time of sampling, the interaction of the mineralized zone with the remnants of mining labors determined an increase in some elements (e.g., Cu ~3 to ~45 mg L−1; As ~0.2 to ~0.5 mg L−1). Dissolved concentrations were controlled by pH, decreasing significantly by precipitation of neoformed minerals (jarosite and schwertmannite) and subsequent metal sorption (~700 mg kg−1 As, 320 mg kg−1 Zn). Dilution also played a significant role (i.e., by the mixing with circumneutral waters which reduces the dissolved concentration and also enhances mineral precipitation). Downstream, most metals exhibited a significant attenuation (As 100 %, Fe 100 %, Zn 99 %). PHREEQC-calculated saturation indices (SI) indicated that Fe-bearing minerals, especially schwertmannite, were supersaturated throughout the basin. All positive SI increased through the input of circumneutral water. PHREEQC inverse geochemical models showed throughout the upper and middle basin, that about 1.5 mmol L−1 of Fe-bearing minerals were precipitated. The modeling exercise of mixing different waters yielded results with a >99 % of correlation between observed and modeled data.Fil: Lecomte, Karina Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Maza, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Collo, Gilda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Sarmiento, A. M.. Universidad de Huelva; EspañaFil: Depetris Gallino, Pedro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentin