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Concept

Commerce

Résumé

Le commerce désigne l'activité économique d'achat et de revente de biens et de services, en particulier l'achat dans le but de revendre avec un profit ou un bénéfice. Le commerce a ses lois propres qui sont recueillies dans les Code de commerce et ses propres juridictions nationales ou internationales. Ayant d'autres finalités que de faire un profit, beaucoup d'activités économiques ou professionnelles comme l'éducation, la police, la culture, la médecine, la justice, l'architecture, la religion, etc. ne relèvent pas du domaine du commerce, mais des lois et des tribunaux civils ou administratif. Avec ses puissants relais d'opinion, l'Organisation mondiale du commerce (OMC) s'efforce d'étendre sa compétence et ses principes de profitabilité sur toutes les activités non commerciales en leur contestant le droit d'avoir des législations et des valeurs désintéressées. Il résulte du mouvement de spécialisation croissante qui affecte les sociétés humaines :

division technique du travai

Source officielle

https://fr.wikipedia.org/wiki/Commerce

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Unités associées (7)

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Cours associés (38)

The course covers a wide range of topics in investment analysis

The course's first part introduces modern methods to acquire, clean, and analyze large quantities of financial data efficiently. The second part expands on how to apply these techniques to financial analysis, in particular to intraday data and investment strategies.

The aim of this course is to expose EPFL bachelor students to some of the main areas in financial economics. The course will be organized around six themes. Students will obtain both practical insights through real-world examples and understand how one can model the main economic trade-offs.

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Cours associés

Chargement

Séances de cours associées (74)

Séances de cours associées

Chargement

A field-based modelling framework of the ecohydrology of schistosomiasis

Francisco Javier Perez Saez

Successful control of schistosomiasis, a water-borne parasitic disease, is challenged by the intricacy of the wormâs lifecycle, which depends on aquatic snail intermediate hosts, and involves environmental, ecologic, and socio-economic factors. Current strategies rely on deworming through mass drug administration which however do not protect against reinfection and the persistence of hotspots. It is recognized that multifaceted approaches will be necessary to reach elimination, whose development will require a renewed focus on the diseaseâs social-ecological drivers. Taking cue from the hydrological underpinning of these drivers, this Thesis aims at developing an ecohydrological approach to schistosomiasis with a view to identifying and exploiting the points in which its cycle can be broken. Schistosomiasis is a poverty-reinforcing disease affecting more than 150 million people in sub-Saharan Africa, being the parasitic disease causing the largest health burden after malaria. However, the impairing morbidity it causes has been undervalued in the past, qualifying it as a neglected tropical disease. Moreover, water resources development often exacerbate transmission, posing scientific and ethical challenges in addressing the ensuing trade-off between economic development and public health. The relevance of this Thesisâ work lies in furthering tools to offset this trade-off by unlocking the predictive appraisal of the social-ecological drivers of transmission. An integration of fieldwork applied in Burkina Faso (West Africa) and theoretical methods are employed to address this aim. This Thesis establishes the use of spatially explicit mathematical models of schistosomiasis at the national-scale, allowing to study the effect of human mobility and spatial heterogeneity of transmission parameters. Weekly ecological samplings of snail abundance and continuous environmental monitoring were preformed at three sites along the countryâs climatic gradient, leveraged through ecological modelling. A novel methodology for the large-scale prediction of river network ephemerality allowed for refined snail species distribution models, and the analysis of the diseaseâs geography in link with socio-economic covariates. Finally, surveys and participatory workshops shed light on local-scale water contact patterns. The obtained results substantiate the stance that hydrology is a first-order control of disease transmission. Stability analysis of the spatially explicit model generated additional insight into the impact of the expansion of suitable snail habitat due to water resources development, highlighting the interplay between local and country-wide effects driven by human mobility. Models of snail ecology revealed key hydrological drivers, and disputed density feedbacks. Uncovered phase shifts between permanent and ephemeral habitats were adequately reproduced at the national scale through model regionalization. Characterization and predictions of hydrological ephemerality improved the estimation of the snailsâ ecological range, mirroring the diseaseâs geography. Finally a national-scale association between ephemerality and disease risk was observed, possibly due to human-water contacts aggregation, as supported by preliminary results at village-level. The future incorporation of these ecohydrological findings into spatially explicit models of schistosomiasis is considered promising for optimizing control strategies and attaining disease elimination.

EPFL2018

Chargement

Corporate disclosure is the most important source of information about the firm for the outside investors. While some disclosure of public firms is mandated by regulation, firm managers can provide extra information at their discretion by making voluntary disclosures. On the other hand, even the reports required by regulation can be disclosed untruthfully. This thesis is structured in three chapters, each addressing a specific issue in voluntary disclosure and misreporting. In the first chapter, titled

Voluntary Disclosure and Informed Trading'', I study the impact of informed trading on voluntary corporate disclosure in the presence of two frictions: cost of disclosure and value of manager's information. In the absence of both frictions, informed trading has no impact on disclosure even when traders are not certain whether the manager has information. If disclosure is costly, then informed trading reduces disclosure. Since traders can discover favorable information about the firm, additional disclosure of the information is not necessary. If manager's information is valuable for the firm, then informed trading increases disclosure. Since traders can discover unfavorable information about the firm, the manager with such information has less incentives to pool with uninformed managers and discloses to show that he is informed. I also show that informed trading can have both a positive and a negative real effect on the firm value by crowding in or crowding out information production in the firm. These results hold for general information structures and are robust if traders can choose how much information to acquire. The second chapter, titled

Misreporting and Feedback Effect'' and co-authored with Prof. Hui Chen of the University of Zurich, studies the incentives of firms to misreport information in the presence of feedback effect from financial markets. Stock price often provides firms with new information, which can be used in the firms' subsequent real decisions. We examine how this informational feedback from the financial market affects a myopic firm manager's incentive to misreport, and how the misreporting further affects the firm's price and value. We find that the manager overstates his report more in the presence of feedback, but this misreporting brings forth both positive price and real effects for the firm. Intuitively, overstating the report encourages information production in the market because (a) it renders accounting reports less reliable as a source of information, and (b) investors expect higher trading profits from larger capital investment. The new incremental information improves investment efficiency when it is revealed to the firm manager through trading and used in the firm's subsequent investment decisions. As a consequence, the capital investment is higher when there is feedback effect. In the third chapter, titled ``Voluntary Disclosure and Margin Constraints'', I develop a dynamic model of voluntary corporate disclosure that explains clustering of negative announcements observed in practice. A manager may receive a signal about the firm's asset value and can disclose it to traders with margin constraints. I show that the manager postpones delivery of a negative signal until the margin constraints tighten. In contrast to previous studies, the clustering of announcements happens even if there are no negative updates in traders' beliefs about the firm value.

EPFL2017

Chargement

This thesis analyzes the interrelation between market structure and price formation in credit derivatives markets. Traditionally, credit derivatives are traded in relatively opaque over-the-counter markets in which trading is segmented and subject to many imperfections from which illiquidity may arise. Recent regulatory reforms have brought transparency to some credit derivatives markets without affecting their segmented structures. The first chapter, which is joint work with Anders B. Trolle, analyzes whether liquidity risk is priced in the cross section of returns on credit default swaps (CDSs). The analysis is based on a factor pricing model and a tradable liquidity factor that is constructed from returns on index arbitrage strategies. The underlying presumption is that violations of simple no-arbitrage relations between different CDS contracts reflect constraints on the risk-bearing capacity of CDS market intermediaries and, in broad terms, CDS market illiquidity. The analysis reveals priced liquidity risk in that credit protection sellers earn higher expected excess returns on CDS contracts with higher liquidity exposures. The liquidity risk premium is significant and accounts for 24% of CDS spreads, on average. CDS risk premia correlate negatively with proxies for the risk-bearing capacity of CDS market intermediaries, which is consistent with intermediary frictions affecting the pricing of CDSs. The second chapter, which is joint work with Pierre Collin-Dufresne and Anders B. Trolle, analyzes transaction costs in the dealer-to-customer (D2C) and dealer-to-dealer (D2D) segments of the post-Dodd-Frank index CDS market. Dodd-Frank regulations that made all-to-all trading possible had the potential to break up the market's segmented structure but failed to do so. This led to a controversy with some market participants arguing that the segmented structure is optimal and other market participants arguing that dealers maintain the segmented structure in order to limit competition by alternative liquidity providers. The analysis reveals that D2C trades indeed have larger transaction costs than D2D trades but that the differences in transaction costs reflect differences in price impacts rather than differences in profits from liquidity provision. D2C trades are even competitive relative to executable bids and offers in the D2D segment, suggesting that the market structure delivers favorable prices for customers who value immediacy. The third chapter documents a decline of transaction costs and profits from liquidity provision in the index CDS market over a two-and-a-half-year period during which Dodd-Frank regulations were implemented. Transaction costs and profits from liquidity provision declined around the introduction of so-called swap execution facilities (SEFs); i.e., regulated trading platforms that offer pre-trade transparent methods of trade execution. Trades that are executed on SEFs have lower transaction costs and are less profitable from a liquidity provider's perspective in comparison to bilaterally negotiated trades, which is consistent with better comparison shopping and stronger price competition on SEFs. Dodd-Frank regulations mandating on-SEF trade execution that were implemented after the introduction of SEFs did not affect transaction costs and profits from liquidity provision, suggesting that there is no incremental effect associated with mandatory pre-trade transparency.

EPFL2016

Chargement

Voluntary Disclosure and Informed Trading'', I study the impact of informed trading on voluntary corporate disclosure in the presence of two frictions: cost of disclosure and value of manager's information. In the absence of both frictions, informed trading has no impact on disclosure even when traders are not certain whether the manager has information. If disclosure is costly, then informed trading reduces disclosure. Since traders can discover favorable information about the firm, additional disclosure of the information is not necessary. If manager's information is valuable for the firm, then informed trading increases disclosure. Since traders can discover unfavorable information about the firm, the manager with such information has less incentives to pool with uninformed managers and discloses to show that he is informed. I also show that informed trading can have both a positive and a negative real effect on the firm value by crowding in or crowding out information production in the firm. These results hold for general information structures and are robust if traders can choose how much information to acquire. The second chapter, titled

EPFL2017

EPFL2016

A field-based modelling framework of the ecohydrology of schistosomiasis

Francisco Javier Perez Saez

EPFL2018