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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only Imported intermediate goods and product innovation(Elsevier B.V., 2024) Şeker, Murat; Rodriguez-Delgado, Jose Daniel; Department of Business Administration; Ulu, Mehmet Fatih; Department of Business Administration; College of Administrative Sciences and EconomicsWe build a structural model of multi-product firms to illustrate how access to foreign intermediate goods contributes to product innovation. We establish a stochastic dynamic model of firm evolution and allow firms to be heterogeneous in their efficiency levels. The model's mechanism to capture the effects of importing intermediate goods is twofold: (i) importing these goods increases the revenue per each product introduced, and (ii) increases the likelihood of introducing new varieties using newly available inputs. We calibrate the model to firm-level data from India. The model successfully explains the heterogeneous innovation dynamics and statistical moments related to importing and product distribution. Counterfactual exercises further illustrate and quantify the mechanism between trade, innovation performance, and product growth. We find that the critical contribution of trade to growth and product innovation is mainly through access to new imported varieties rather than just the direct import cost. © 2024 Elsevier B.V.Publication Metadata only On the past, present, and future of the Diebold-Yilmaz approach to dynamic network connectedness(Elsevier Science Sa, 2023) Diebold, Francis X.; Department of Economics; Yılmaz, Kamil; Department of Economics; College of Administrative Sciences and EconomicsWe offer retrospective and prospective assessments of the Diebold-Yilmaz connected-ness research program, combined with personal recollections of its development. Its centerpiece in many respects is Diebold and Yilmaz (2014), around which our discussion is organized.Publication Metadata only On the network topology of variance decompositions: measuring the connectedness of financial firms (Reprinted from Journal of Econometrics, Vol 182, Issue 1, September 2014, Pages 119-134)(Elsevier Science Sa, 2023) Diebold, Francis X.; Department of Economics; Yılmaz, Kamil; Department of Economics; College of Administrative Sciences and EconomicsWe propose several connectedness measures built from pieces of variance decomposi-tions, and we argue that they provide natural and insightful measures of connectedness. We also show that variance decompositions define weighted, directed networks, so that our connectedness measures are intimately related to key measures of connectedness used in the network literature. Building on these insights, we track daily time-varying connectedness of major U.S. financial institutions' stock return volatilities in recent years, with emphasis on the financial crisis of 2007-2008.Publication Metadata only Economic costs of friendshoring(Wiley, 2024) Javorcik, Beata; Kitzmueller, Lucas; Schweiger, Helena; Department of Economics; Yıldırım, Muhammed Ali; Department of Economics; College of Administrative Sciences and EconomicsGeo-political tensions and disruptions to global value chains have led policymakers to re-evaluate their approach to globalisation. Many countries are considering friendshoring - trading primarily with countries sharing similar values - as a way of minimising exposure to weaponisation of trade and securing access to critical inputs. If followed through, this process has the potential to reverse global economic integration of recent decades. This article estimates the economic costs of friendshoring using a quantitative model incorporating inter-country inter-industry linkages. The results suggest that friendshoring may lead to real GDP losses of up to 4.7% of GDP in some economies. Thus, although friendshoring may provide insurance against extreme disruptions and increase the security of supply of vital inputs, it would come at a substantial cost.Publication Metadata only Is there a virtuous cycle between wages and productivity? Turkish experience after the transition to democracy(Elsevier Ltd, 2024) Taymaz, Erol; Voyvoda, Ebru; Department of Economics; Yılmaz, Kamil; Department of Economics; College of Administrative Sciences and EconomicsWe analyze the behavior of plant-level real wages and productivity in Turkish manufacturing after the transition to democracy in 1987 and test for the direction of the causality between these two variables. The Turkish experience is almost an experimental case because successive governments after 1987 let real wages increase rapidly under the pressure of intensifying political competition. Real wages in state-owned enterprises increased by nearly 200% from 1988 to 1993, followed by a 130% increase in real wages in private manufacturing. Our analysis shows that labor and total factor productivity increased at an unprecedented rate during the same period in response to the exogenous wage hikes. Econometric estimates provide strong empirical evidence supporting the hypothesis that there is a bi-directional relationship between wages and productivity, and wage increases do not reduce surplus because the increase in productivity (value added per worker) compensates for increasing wages. © 2023 Elsevier LtdPublication Metadata only Relief item inventory planning under centralized and decentralized bilateral cooperation and uncertain transshipment quantities(Elsevier Science Inc, 2024) Coşkun, Abdullah; Department of Industrial Engineering; Salman, Fatma Sibel; Pashapour, Amirreza; Department of Industrial Engineering; College of Engineering; Graduate School of Sciences and EngineeringPre-positioning relief inventory ensures timely delivery of in-kind aid after a catastrophe. Tragic disasters like major earthquakes are rare and unpredictable;therefore, stockpiled items may not be used. To avoid overstocking and reduce shortage risk, the cooperation of two humanitarian agencies in supporting each other in case of shortages is suggested in the literature. In this study, we utilize newsvendor-based quantitative models to optimize the pre-disaster stocking decisions of agencies under centralized and decentralized cooperation mechanisms. In the former, both agencies jointly determine their inventory levels to maximize their combined benefits of relief operations, whereas, in the latter, each agency establishes its stocking level in isolation via a game theoretic approach. In both systems, the two agencies agree to transship their excessive items to the other party if needed. In this regard, we investigate the situation where only a portion of the transshipped items, denoted as the reliability factor, can be received and effectively utilized at the destination due to the chaotic nature of the disaster. Considering a deterministic reliability factor, we obtain the singular optimal inventory levels in the centralized system and identify the unique Nash Equilibrium in the decentralized system. Subsequently, we formulate a two-stage stochastic program, considering a random reliability factor for both cooperation systems. The study concludes by offering a range of managerial insights. Our analyses quantify the sub-optimality resulting from decentralized decision-making across diverse parameter settings using the concept of the price of anarchy. The findings highlight that centralized cooperation becomes particularly advisable when the average demand within either agency is high, the transshipment process is secure (i.e., the reliability factor is high), and transshipment costs remain low.Publication Metadata only Fair and effective vaccine allocation during a pandemic(Elsevier Science Ltd, 2024) Erdoğan, Güneş; Yücel, Eda; Department of Industrial Engineering; Kiavash, Parinaz; Salman, Fatma Sibel; Department of Industrial Engineering; Graduate School of Sciences and Engineering; College of EngineeringThis paper presents a novel model for the Vaccine Allocation Problem (VAP), which aims to allocate the available vaccines to population locations over multiple periods during a pandemic. We model the disease progression and the impact of vaccination on the spread of the disease and mortality to minimise total expected mortality and location inequity in terms of mortality ratios under total vaccine supply and hospital and vaccination centre capacity limitations at the locations. The spread of the disease is modelled through an extension of the well -established Susceptible-Infected-Recovered (SIR) epidemiological model that accounts for multiple vaccine doses. The VAP is modelled as a nonlinear mixed -integer programming model and solved to optimality using the Gurobi solver. A set of scenarios with parameters regarding the COVID-19 pandemic in the UK over 12 weeks are constructed using a hypercube experimental design on varying disease spread, vaccine availability, hospital capacity, and vaccination capacity factors. The results indicate the statistical significance of vaccine availability and the parameters regarding the spread of the disease.Publication Metadata only Banks as the new family: the transition from informal to formal borrowing in Turkey(Routledge Journals, Taylor & Francis Ltd, 2024) Kılınçarslan, Pelin; Migration Research Program at Koç University (MIReKoç) / Göç Araştırmaları Uygulama ve Araştırma Merkezi (MIReKoç)This paper focuses on the impact of social reproduction patterns on borrowing experiences in everyday life, linking two lines of research within feminist and critical International Political Economy (IPE) literature of the everyday, one on social reproduction and debt, and the other on financial subjectivities. Drawing on interviews with women from indebted households in Istanbul, Turkey, it specifically explores how this impact is reflected in the meanings attached to borrowing and the perceptions of what it entails to be a debtor, thereby generating gendered implications. This article reveals that borrowing from family and friends, once seen as an expression of trust and solidarity, is now associated with financial dependence and humiliation, while borrowing from banks is perceived as a means to achieve self-reliance and self-responsibility. However, these meanings contradict women's self-identifications as debtors, which are framed in moral terms surrounding the structural necessity of incurring credit-debt for social reproduction. This paper contributes to political economy scholarship by addressing how the everyday lives of the indebted are linked to the broader global financial system, mediated by the specific conditions of a Global South context (Turkey) characterized by subordinate financialization, the political use of credit expansion, and a neoliberal/conservative gender regime.Publication Metadata only You will: a macroeconomic analysis of digital advertising(Oxford University Press, 2024) Greenwood, Jeremy; Ma, Yueyuan; Department of Economics; Yörükoğlu, Mehmet; Department of Economics; College of Administrative Sciences and EconomicsAn information-based model is developed where traditional and digital advertising finance the provision of free media goods and affect price competition. Digital advertising is directed toward specific consumers while traditional advertising is undirected. The equilibrium is suboptimal. Media goods, if valued by the consumer, are under provided with both types of advertising. Additionally, traditional advertising is excessive because it is undirected. The tax-cum-subsidy policy that overcomes these inefficiencies is characterized. The model is calibrated to the U.S. economy. Through the lens of the calibrated model, digital advertising increases welfare significantly. The welfare gain from the optimal policy is much smaller than the gain from digital advertising.Publication Metadata only Brands and branding around the World(Sage Publications Inc, 2024) Batra, Rajeev; Steenkamp, Jan-Benedict E. M.; Department of Business Administration; Tunalı, Ayşegül Özsomer; Department of Business Administration; College of Administrative Sciences and EconomicsN/A