Economics | EPFL Graph Search

Economics (ˌɛkəˈnɒmᵻks,_ˌiːkə-) is a social science that studies the production, distribution, and consumption of goods and services. Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analyzes what's viewed as basic elements in the economy, including individual agents and markets, their interactions, and the outcomes of interactions. Individual agents may include, for example, households, firms, buyers, and sellers. Macroeconomics analyzes the economy as a system where production, consumption, saving, and investment interact, and factors affecting it: employment of the resources of labour, capital, and land, currency inflation, economic growth, and public policies that have impact on these elements. Other broad distinctions within economics include those between positive economics, describing "what is", and normative economics, advocating "what ought to be"; between economic theory and applied economics; between rational

'Peak Oil' As Classical Economic Process

François Meynard

Forecasts about 'peak oil', the limits of oil production, are the subject of controversies. 'Peak oil' forecasts are based on extrapolations of a priori chosen mathematical models fitted to field data. Scientifically that is not very sound. To clarify this point, in this paper 'peak oil' is modelled in a generic reductionist, approach, in which the conflicting dynamic between economic forces and physical laws are well identified. This model finds a natural interpretation just supress in a classical economic analysis frame. The 'peak oil' controversy is thus brought into the field of economic thought as a debate between classical and mainstream economics, in particular between an objective and a faith based appraisal about this historical event. The goal is not to improve forecasts about 'peak oil', which is very likely not a predictable event, but to propose an objective framework for the analysis of its systemic effects on economic production.

Multi-Science Publ Co Ltd2014

Vieillissement et fiabilité des parcs de poteaux bois des réseaux de lignes aériennes

Yann Benoit

The reliability of new overhead electric and telecommunication lines depends principally on the quality of their support structures. These structures are generally made of wood, metal or concrete. The complexity of a natural substance such as wood requires a thorough analysis of the various factors that influence its overall quality. In the case of wood poles, such factors include initial forest growth pattern, the species of wood and its preservative treatment, ageing characteristics, and its various mechanical defects such as knots, cracks etc. The accumulation of knowledge on the effect of the various variables that contribute to the overall quality of a wood support structure permits an optimum use of such a resource. For example, less variability and higher strength of wood support structures permits optimum loading and spacing between structures, thus reducing the number needed in a specific length of an overhead line. If one assumes that in Western Europe 1 wood pole is employed for every 2 inhabitants, and that this proportion increases in less densely populated countries such as the US and Scandinavia, the economics of optimum use of wood as a resource soon become apparent. In less developed countries, the proportions and the economics vary depending on the natural resources such as wood that they employ. The goal of this research is to establish, thanks to non destructive evaluations, a general ageing probabilistic law of the wooden pole based on two distinguished laws: one on the new pole in studying the influence of a grading of the bad elements based on a normal law: "left-truncation of a normal distribution", point 1; and another one based on the in-field wooden pole in exploiting the different parameters such as: the age of the pole, its chemical treatment, its species, its knots etc. in order to define the pole's damage law, point 2. Statistical distribution law of the new wooden pole after grading by non destructive sorting (ultrasounds) of the high mechanical performances supports: This new distribution law is a Gaussian law or evolves to a Log or Weibull's law with 3 parameters according to the inspected species. This grading allows a revalorization of the properties of the new poles and of the design values while guaranteeing an index of reliability required by the design standards, or in improving directly this nominal reliability (economic gain and reliability gain). Statistical distribution law of an aged in-field population (20-50 years old) approached by a bi-modal law which depends on: The distribution law of the new component (see point 1) and its minimal extreme law, which is asymmetrical, for an observation on 50 years. The statistical distribution at the time t of the residual mechanical performances of a group of supports making a local net, evaluated by non destructive methods. The non destructive evaluation is based on the measurements of physical variables (density, biological moisture content) and some descriptive variables from natural origins (diameter, knots, cracks...) and from accidental origins (diameter reduction, lightning cracks...). The statistical distribution at the time t is then obtained on the basis of a model of multivariate non destructive evaluation, generalized to the whole of species and treatments. This model is the other concrete goal to reach in this thesis. As a conclusion, the research demonstrates the influence and the interaction of the new pole grading (distribution at t0) on the modelisation of the distribution at ti (multivariate non destructive model). The data used for the mentioned modelisations come from a significant international database with a large amount of inspected wood poles and with studied cases. This database is the synthesis of about 15 years of research and development leaded by IBOIS-EPFL and its international partners. The probabilistic approaches are then validated by a huge database allowing thus to be directly exploitable. On this basis, all the standards dealing with the new poles and dealing with the controls and maintenances of a wooden pole networks, could be re-examined for a double gain: Concerning the economy: by increasing the capacity of the new poles profiting of an objective quality assurance, and by increasing the life time of the in-field pole, in knowing how to purge only the ones which are under the critical threshold of damage Concerning the reliability: by increasing the reliability of the network from the stage "new pole", by eliminating the weakest components, and by maintaining this reliability during all the life time of the network thanks to a cyclic preventive maintenance (every 5 to 8 years) and the replacement of only the weakened poles.

EPFL2004

Essays on Mortgage Supply in a Low Rate Environment and Gender Effects of Covid-19

Yu Wu

After the financial crisis, policy rates in the major advanced economies have moved downwards to near/below zero. Some countries have experienced an increase in house prices and an expansion of mortgages. Also, there have been considerable changes in the mortgage market share, with only a few bank categories contributing to this mortgage expansion. Such change in exposure to real estate risk may pose a risk to financial stability. My dissertation research studies the role played by specific bank features, such as reliance on deposits and covered bonds or capital surplus relative to the required level, in explaining banks' different mortgage lending behavior. The first chapter (joint with Prof. Luisa Lambertini) studies the Swiss mortgage market dynamics in a low rate environment. After 2008, small banks (cantonal banks and Raiffeisen) have primarily contributed to this mortgage expansion at the expense of two big global systemic banks (UBS and Credit Suisse). We set up a model featuring big and small banks that compete in the deposit and mortgage market and face different capital requirements. We calibrate it to the Swiss banking sector. In this model, a falling policy rate drives up borrowing demand and leads to an expansion in mortgage supply; however, an asymmetric tightening of capital requirement gives small banks a competitive advantage and causes a shift in market share towards small banks. In the second chapter, with Prof. Luisa Lambertini, we use the Swedish bank-level data and employ a triple diff strategy to investigate whether funding side differences also play a role in explaining banks' different lending responses to the negative rate policy. First, we find that high-deposit banks expand their mortgage supply less than low-deposit banks during negative rate periods, confirming the well-documented deposit channel effect. However, this pattern works only for weakly-capitalized banks, which have a low capital buffer. Second, we show that banks more reliant on covered bonds to finance mortgage lending lend out more under negative rates; they can shift into cheap deposits to reduce their funding costs. We extend our model in the first chapter to be consistent with these empirical findings and use it to study the implications of the Covid-19 pandemic for the mortgage market. The third chapter analyzes the transmission of housing price dynamics to the real economy in the context of China, which went through a decade-long housing boom. Understanding its propagation to other economic activities is thus important. I build up a real business cycle model for this study and find that land-use conversion by the governments and land finance of housing firms can amplify the crowding-out effects of housing price fluctuations on the non-housing sector. The year 2020 was marked by the outbreak of the Covid-19 pandemic, which adversely affected the labor market. The fourth chapter is an additional line of work, with Dr. Corinne Dubois and Prof. Luisa Lambertini exploring gendered consequences of the pandemic in the Swiss labor market. We use the Swiss labor force survey data and find that all else equal, women have been more likely to exit the labor market altogether or to use short-term working schemes than their male counterparts. Contrary to expectations, increased family-care responsibility is not the main driver. Telework availability of occupation, however, explains some of the differential impact of Covid-19 on men and women.

EPFL2021