Produit intérieur brut | EPFL Graph Search

Le produit intérieur brut (PIB) est l'indicateur économique qui permet de quantifier la valeur totale de la « production de richesse » annuelle effectuée par les agents économiques (ménages, entreprises, administrations publiques) résidant à l'intérieur d'un territoire. Le produit intérieur brut est le principal indicateur de la mesure de la production économique réalisée à l’intérieur d'un pays et l'un des agrégats majeurs des comptes nationaux. Le PIB reflète donc l'activité économique interne d'un pays et la variation du PIB d'une période à l'autre est censée mesurer son taux de croissance économique. Il diffère du revenu national brut (RNB) qui ajoute au PIB (produit intérieur brut) les entrées nettes de revenus de facteurs en provenance de l'étranger (revenus de facteurs provenant du reste du monde diminués des revenus de facteurs payés au reste du monde). La composition de cet indice est dans certains cas sujette à caution ou à suspicion, en particulier lorsque les gouverne

Essays in Financial Economics

Christoph Helmut Peter Herpfer

This thesis contains four chapters, each of which utilizes new or unusual data sources to analyze a different area of financial economics. In the first chapter, I construct a novel dataset linking individual bankers to large borrowers in the U.S. syndicated loan market to analyze the impact of bankers on bank lending. I find that time invariant banker fixed effects have at least as much explanatory power as bank fixed effects across key loan outcome variables. One channel through which bankers impact lending is through personal relationships with borrowers. I address the endogenous nature of relationship formation by exploiting shocks to relationships from the departure of bankers and find that stronger personal relationships are associated with significantly lower interest rates charged to clients. Reduced interest rates of relationship loans reflect superior information of bankers, rather than nepotism. Loans issued by bankers that have stronger personal relationships with borrowers are associated with fewer bankruptcies and no more beneficial terms upon renegotiation. The second chapter, which is joint work with Stefano Colonnello, exploits a U.S. Supreme Court ruling on diversity of citizenship in legal disputes to estimate the contribution of the court system to firm value. In an event study, we find that an increase in state court quality from bottom to top tercile is associated with an average increase in equity value of 0.45%, or about $8.7 million on the event day. This effect appears to be driven by courts¿ attitude towards businesses more than by their competency and is more pronounced for firms in industries with high litigation risk. We also test whether firms benefit from the ability to steer lawsuits into friendly courts, so called forum shopping. We provide evidence that a reduction in firms¿ ability to forum shop decreases firm value, whereas a reduction in plaintiffs¿ ability to forum shop increases firm value. We further document that the ruling had significant real effects. Firms which previously stayed out of regions with potentially problematic courts subsequently increased their operations in those regions. The third chapter is coauthored with Matthias Effing, Rüdiger Fahlenbrach, and Philipp Krüger and examines the impact of a sudden home currency appreciation on the valuation and behavior of corporations in a developed economy. The Swiss National Bank surprisingly repealed the minimum exchange rate of 1.2 Swiss francs per Euro on January 15, 2015. On that day the franc appreciated by 15% and the main stock market index dropped by 8.7%. The impact was largest for export oriented firms with high domestic costs. These firms experienced 5% lower announcement returns, subsequently faced economically sizeable reductions in sales and profitability, and responded by reducing investment by 8.1% while only slightly reducing employment. In the fourth chapter, which is joint work with Cornelius Schmidt and Aksel Mjøs, we exploit exogenous shocks to the distance between corporate borrowers and banks to analyze the role of distance in commercial bank lending. We find that a reduction in travel time due to improved infrastructure increases the likelihood of initiating a new borrowing relationship, evidence that closer distance creates a surplus from lower transaction costs. In existing lending relationships, however, banks capture a fraction of this surplus by increasing interest rates.

EPFL2017

Robust Multivariate and Nonlinear Time Series Models

Time series modeling and analysis is central to most financial and econometric data modeling. With increased globalization in trade, commerce and finance, national variables like gross domestic productivity (GDP) and unemployment rate, market variables like indices and stock prices and global variables like commodity prices are more tightly coupled than ever before. This translates to the use of multivariate or vector time series models and algorithms in analyzing and understanding the relationships that these variables share with each other. Autocorrelation is one of the fundamental aspects of time series modeling. However, traditional linear models, that arise from a strong observed autocorrelation in many financial and econometric time series data, are at times unable to capture the rather nonlinear relationship that characterizes many time series data. This necessitates the study of nonlinear models in analyzing such time series. The class of bilinear models is one of the simplest nonlinear models. These models are able to capture temporary erratic fluctuations that are common in many financial returns series and thus, are of tremendous interest in financial time series analysis. Another aspect of time series analysis is homoscedasticity versus heteroscedasticity. Many time series data, even after differencing, exhibit heteroscedasticity. Thus, it becomes important to incorporate this feature in the associated models. The class of conditional heteroscedastic autoregressive (ARCH) models and its variants form the primary backbone of conditional heteroscedastic time series models. Robustness is a highly underrated feature of most time series applications and models that are presently in use in the industry. With an ever increasing amount of information available for modeling, it is not uncommon for the data to have some aberrations within itself in terms of level shifts and the occasional large fluctuations. Conventional methods like the maximum likelihood and least squares are well known to be highly sensitive to such contaminations. Hence, it becomes important to use robust methods, especially in this age with high amounts of computing power readily available, to take into account such aberrations. While robustness and time series modeling have been vastly researched individually in the past, application of robust methods to estimate time series models is still quite open. The central goal of this thesis is the study of robust parameter estimation of some simple vector and nonlinear time series models. More precisely, we will briefly study some prominent linear and nonlinear models in the time series literature and apply the robust S-estimator in estimating parameters of some simple models like the vector autoregressive (VAR) model, the (0, 0, 1, 1) bilinear model and a simple conditional heteroscedastic bilinear model. In each case, we will look at the important aspect of stationarity of the model and analyze the asymptotic behavior of the S-estimator.

EPFL2010

Innovation capacity of the agricultural sector: network of productive interactions, knowledge transfer and differentiation mechanisms

Camille Marguerite Aouinait

Economic growth is increasingly explained and driven by knowledge acquisition and firmsâ capabilities to adapt to new evolving situations to fit economic, societal and environmental frames. Strategic behavior of private companies in differentiating and promoting their products and services is crucial for their competitiveness. In parallel, public research performed at different territorial levels and by a high diversity of actors is a strategic source of key assets adding value to the firms. External actors operate in a non-linear structure allowing frequent feedback and interactive loops in order to optimise the replies to substantial problems and constantly valorise their resources. These features are explored in the thesis through different projects. This dissertation is motivated by international negotiations in the frame of the GATT agreements and bilaterally between the European Union and Switzerland that are going towards the breakdown of borders, threatening the competitiveness of the Swiss agriculture. Negative externalities will affect small firms composing this agricultural network. Thus, the dissertation is focusing on innovation as a strategic asset to maintain the competitiveness and differentiate the domestic agricultural products. The first research project concentrates on interactions occurring in the Swiss apricot network. We investigate the types of interactions producing innovations that come from different sources that are internal or external to the agricultural production supply chain. We use network theory to model the structure of the domain and understand what is inherent to innovation production thanks to collaborations through an empirical work. In the second research project, we examine whether there is a connection between the issues faced by small companies producing food and the innovative solutions and knowledge generated by research institutions. The importance of solutions to daily activities conducted by companies depends on the nature of the sector. Thus, research projects providing outputs like publications might not specifically target these issues. Moreover, access, awareness and affordability of innovations can be hindering factors for small firms composing a low-technology intensive sector. Gaps of knowledge transfer, innovation and implementation are identified in this setting. In the last research project, we address market failures hampering economic and strategic management decisions encountered in the agricultural sector. We empirically construct two case studies highlighting the necessity of intellectual appropriation mechanisms. We explore the use of patents and regional trademark to add value to the emblematic product of a small region. Organisational and marketing innovations have to be supported and diffused by key stakeholders, aiming a good communication based on criteria that take into account diverse interests of those stakeholders; consumers have to be involved in the innovation process. Furthermore, knowledge transfer, innovation generation, diffusion and implementation rely upon the will of stakeholders to take part in an efficient process of interactions and communication in order to produce and perform useful products and services. Practical implications are levered in the projects presented. Finally, digital technologies are efficient for information exchange and can decrease time and transaction costs. These technologies are explored as part of the solution to small firmsâ

EPFL2019