Three essays on dynamic models with applications in marketing and finance

Cette thèse se compose de trois chapitres qui présentent trois articles indépendants portant sur l’application de modèles dynamiques dans les domaines du marketing et de la finance. Le premier article adopte une approche structurelle des modèles dynamiques pour analyser la relation entre les revenus et l’impact des taxes sur les produits de grignotage (fat taxes). Le deuxième et le troisième article utilisent des modèles dynamiques en forme réduite : nous y mobilisons des modèles hiérarchiques dynamiques qui intègrent un cadre bayésien hiérarchique à un Modèle Linéaire Dynamique. Le second article étudie la tarification dynamique des produits de saison à l’aide d’un modèle hiérarchique dynamique et flexible. Le troisième article analyse le coût du financement des opérations commerciales au cours de la crise financière de 2008-2009 au moyen d’un modèle hiérarchique dynamique. Dans le premier article, nous utilisons un modèle structurel dynamique pour analyser la corrélation entre les revenus et l’impact d’une taxe sur les produits de grignotage (ou fat tax). Les résultats montrent qu’une telle taxe a moins d’impact sur les individus à faibles revenus que sur ceux dont les revenus sont plus élevés, dans la mesure où le premier groupe a davantage tendance à consommer des snacks. Dans le second article, nous élaborons un modèle hiérarchique dynamique et flexible pour estimer la trajectoire des sensibilités-prix afin d’en déduire le tarif dynamique des produits de saison. Nous constatons que les prix optimaux dépendent de la composition de la clientèle du magasin, et que les vendeurs de produits de saisons peuvent en tirer profit lorsqu’ils fixent leurs tarifs. Dans le troisième article, nous utilisons un modèle hiérarchique dynamique pour étudier l’impact de quatre indicateurs macroéconomiques sur le coût du financement des opérations commerciales pendant la crise financière de 2008-2009, ainsi que pendant les périodes qui l’ont précédée et suivie. Nous constatons que l’impact de trois de ces facteurs macroéconomiques (croissance du PIB, échanges commerciaux et inflation) sur le financement commercial est conforme aux prédictions théoriques, tandis que l’impact du quatrième facteur (capitalisation boursière) semble assez surprenant.This dissertation consists of three chapters that present three standalone essays on the application of dynamic models to marketing and finance. The first essay uses a structural approach to dynamic models to study the role of income on the impact of fat taxes. The second and third essays use a reduced form approach to dynamic models: we use dynamic hierarchical models which incorporate a Hierarchical Bayesian framework in a Dynamic Linear Model. The second essay studies the dynamic pricing of seasonal goods with the help of a flexible dynamic hierarchical model. The third essay studies the cost of trade finance during the financial crisis of 2008-2009 using a dynamic hierarchical model. In the first essay, we use a dynamic structural model to investigate how income interacts with the impact of a “fat tax” (a tax on snack food). We find that the low-income group is less impacted by a “fat tax” compared to the higher income group as they have a higher tendency to consume snack food. In the second essay, we develop a flexible dynamic hierarchical model to estimate the trajectory of price sensitivities which allows us to infer the dynamic prices of seasonal goods. We find that optimal prices depend on the customer composition of the store, and seasonal goods retailers can take advantage of this while setting prices. In the third essay, using a dynamic hierarchical model we examine the impact of four macroeconomic indicators on trade finance costs in and around the financial crisis of 2008-2009. We find the impact of three of these macroeconomic factors (GDP growth, trade and inflation) on trade finance to be in line with the theory, while the impact of the fourth factor (stock market capitalization) on trade finance appears somewhat surprising

Surviving the hectic early phase of the COVID-19 pandemic:a qualitative study to the supply chain strategies of food service firms in times of a crisis

Purpose The COVID-19 pandemic and the subsequent lockdown have hit the food service industry very hard. The COVID-19 outbreak has created a sharp downturn for firms in the food service industry, compelling actors across the whole food service supply chain to rethink their strategies. The purpose of this paper is to document the impact of COVID-19 on the food service supply chain, as well as to identify crisis management strategies food service firms use during the hectic early phase of the COVID-19 pandemic to survive the current and prepare for future pandemics. Design/methodology/approach We performed a qualitative descriptive study using 21 semi-structured interviews with actors across the food service supply chain (i.e. farmers, wholesalers and food service providers). Data were collected to shed light on food service firms' decision making during the hectic early phase of the COVID-19 pandemic to uncover various crisis management strategies used. Findings By integrating the disaster and crisis pyramid and resilience theory, four core crisis management strategies to respond to the COVID-19 pandemic are conceptualized, i.e. (1) managing resources, (2) diversifying strategically, (3) prioritizing long-term outcomes and (4) bonding socially. Originality/value The theoretical contributions include documenting the performance impact of the COVID-19 pandemic on the food service supply chain and exploring crisis management strategies food service firms employed during the hectic early phase of the COVID-19 pandemic. Thus, functioning and survival during a pandemic, an emerging field in literature, are central to this study. Additionally, while recent research suggests that integrating crisis management and resilience literature may provide a more complete understanding of the organization-crisis relationship, these literature streams mainly developed in isolation. By integrating the literature streams of crisis management and resilience and applying these theories to the COVID-19 crisis, our study provides specific managerial guidelines

Reducing food waste through digital platforms:A quantification of cross-side network effects

To fight food waste, retail stores have begun selling perishable food close to the expiration date at discounted prices. To render this form of last-minute discounting effective, digital platforms have been developed with the major aim to connect local retail stores and their consumers by sharing information about these discounts. To sustain digital platforms, platform leaders need to ensure both consumers and retail stores remain active on it. To provide platform leaders with advice on how to create a sustainable digital platform, we examine how retail store activity on the digital platform affects consumer activity, and vice versa (also known as cross-side network effects). By combining a PVAR model and an impulse response function, along with data from a digital platform aimed at food waste reduction, we find that the effect of consumer activity on retail store activity is stronger and more long-lasting than the effect of retail store activity on consumer activity. We discuss the implications of our findings for both retail stores and digital platform leaders

An Outcome Based Exploration of Pharmacotherapeutics in Chronic Mechanical Non-Specific Low Back Pain (CNLSBP) Patients in Tertiary Care Hospital

Background: Low back pain is a symptomatic condition with multifactorial causation. It is characterized by pain & muscle stiffness or tension. The aim of management of low back pain is to relieve the pain quickly, to improve functional ability & prevention of disability. A range of Non-Steroidal Anti-Inflammatory drugs (NSAIDs) are used for management which provides variable symptomatic relief.Aims and objectives: To evaluate the pattern and prescribing trends of therapy with different NSAIDS & to evaluate the efficacy of different pharmacotherapeutics in the management of chronic mechanical nonspecific low back pain by using visual analogue scale (VAS) score and Oswestry Disability Index (ODI) score.Materials and methods: This prospective, observational, and questionnaire-based study was conducted in the Department of Physical Medicine and Rehabilitation center (PMR) of RG Kar Medical College and Hospital, Kolkata. 130 newly diagnosed CNSLBP patients were selected after satisfying inclusion and exclusion criteria. NSAIDs involved in the study are Aceclofenac, Paracetamol, Ibuprofen, Etodolac, Etoricoxib, Naproxen, Piroxicam. Mean VAS score and ODI score were evaluated in all patients at 0, 4, 8 and 12 weeks to assess the efficacy of NSAIDs in reducing pain and functional disability. Results: Among 130 patients involved in the study, 84(65%) were female and 46(35%) were male patients and the mean age of female was 40.46 and that of male was 39.96 years. All the different NSAIDS involved in this study were effective in reducing pain and functional disability in CNSLBP patients as evaluated by VAS score and ODI score