Prix | EPFL Graph Search

Le prix, exprimé en un montant de référence (en général monétaire), est la traduction de la compensation qu'un opérateur est disposé à remettre à un autre en contrepartie de la cession d'un bien ou un service. Le prix mesure la valeur vénale d'une transaction et en constitue l'un des éléments essentiels. Détermination Le mécanisme de formation des prix est un des concepts centraux de la microéconomie, spécialement dans le cadre de l'analyse de l'économie de marché, où les prix jouent un rôle primordial dans la recherche et la définition d'un prix dit « d'équilibre » (alors qu'ils jouent un rôle plus mineur dans une économie administrée). Les niveaux de prix possibles sont en nombre potentiellement infini, selon les acteurs économiques, selon leurs estimations de la valeur de la chose pour eux-mêmes et pour les autres (spéculation). Si une transaction se réalise effectivement, le prix traduit le compromis entre les estimations de l'acheteur et celles du vendeur (reflet de

Polynomial models in finance

Damien Edouard Ackerer

This thesis presents new flexible dynamic stochastic models for the evolution of market prices and new methods for the valuation of derivatives. These models and methods build on the recently characterized class of polynomial jump-diffusion processes for which the conditional moments are analytic. The first half of this thesis is concerned with modelling the fluctuations in the volatility of stock prices, and with the valuation of options on the stock. A new stochastic volatility model for which the squared volatility follows a Jacobi process is presented in the first chapter. The stock price volatility is allowed to continuously fluctuate between a lower and an upper bound, and option prices have closed-form series representations when their payoff functions depend on the stock price at finitely many dates. Truncating these series at some finite order entails accurate option price approximations. This method builds on the series expansion of the ratio between the log price density and an auxiliary density, with respect to an orthonormal basis of polynomials in a weighted Lebesgue space. When the payoff functions can be similarly expanded, the method is particularly efficient computationally. In the second chapter, more flexible choices of weighted spaces are studied in order to obtain new series representations for option prices with faster convergence rates. The option price approximation method can then be applied to various stochastic volatility models. The second half of this thesis is concerned with modelling the default times of firms, and with the pricing of credit risk securities. A new class of credit risk models in which the firm default probability is linear in the factors is presented in the third chapter. The prices of defaultable bonds and credit default swaps have explicit linear-rational expressions in the factors. A polynomial model with compact support and bounded default intensities is developed. This property is exploited to approximate credit derivatives prices by interpolating their payoff functions with polynomials. In the fourth chapter, the joint term structure of default probabilities is flexibly modelled using factor copulas. A generic static framework is developed in which the prices of high dimensional and complex credit securities can be efficiently and exactly computed. Dynamic credit risk models with significant default dependence can in turn be constructed by combining polynomial factor copulas and linear credit risk models.

EPFL2017

Asset Pricing and Monetary Policy

Nicolas Gauderon

Classical theory asserts that the formation of prices is the result of aggregated decisions ofeconomics agent such as households or corporation. However central banks are very importantagents that have often been neglected in asset pricing models. Central banks decisions ormonetary policy indeed appears to be a first order determinant of prices.This thesis aims to develop an asset pricing model that explicitly incorporates a central bankand to analyze the determination of monetary policy and its impact on financial markets. Myresults should help to improve our understanding of asset prices in the context of a monetaryeconomy. Therefore results should help both to improve portfolio management in presenceof an active monetary policy and to give central bankers a better understanding of their ownmarket impact thus helping them to design better monetary policy.

EPFL2022

Three Essays on Corporate Disclosure

Evgeny Petrov

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

Polynomial models in finance

Damien Edouard Ackerer

EPFL2017

Three Essays on Corporate Disclosure

Evgeny Petrov

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