LING Julien

This thesis aims at studying systemic risk in commodity futures markets. A whole strand of the literature is dedicated to the "financialization of commodity markets", but also to the influence of the existence of futures markets on the spot price of their underlying asset. Indeed, since these commodity futures have been largely used by in asset management as diversifying assets, their financialization has raised concerns, especially seeing the evolution of their price, which seems to be similar to that of financial assets. My interest here is thus to quantify this systemic risk, provide a toolbox to assess the consequences of various scenarios (stress tests), but also to assess which markets should be monitored more closely (because they could threaten the real economy or the whole system).

This thesis aims to analyze the systemic risk on commodity futures markets. Indeed, several research works highlight the importance of these futures in the determination of the physical price of commodities. Their incorporation into traditional finance as a diversifying asset has led to a similar price evolution to that of various financial assets since about 2004. The question that motivated this thesis was therefore to quantify this systemic risk (since it affects commodities, which are directly involved in the real economy), to see precisely the means of transmission (which markets affect which other markets) and finally to allow for an evaluation of the consequences, for example, based on scenarios (stress tests). It therefore makes it possible to develop market surveillance tools and could therefore contribute to the regulation of these markets.

We examine the impact of two financial crises on commodity derivative markets: the subprime crisis and the bankruptcy of Lehman Brothers. These crises are "external" to the commodity markets because they occurred in the financial sphere. Still, because commodity markets are now highly integrated with each other and with other financial markets, such events could have had an impact. In order to fully comprehend this possible impact, we rely on tools inspired by the graph theory that allow for the study of large databases. We examine the daily price fluctuations recorded in 14 derivative markets from 2000 to 2009 in three dimensions: the observation time, the space dimension – the same underlying asset can be traded simultaneously in two different places – and the maturity of the transactions. We perform an event study in which we first focus on the efficiency of the price shock’s transmission to the commodity markets during the crises. Then we concentrate on whether the paths of shock transmission are modified. Finally, relying on the measure proposed by Bonacich (1987) for social networks, we focus on whether the centrality of the price system changes.

We examine the impact, on commodity derivative markets, of two financial crises: the Subprime crisis and the bankruptcy of Lehman Brothers. These crises are "external" for commodity markets: they appeared in the financial sphere. Still, because now commodity markets are highly integrated, between themselves and with other financial markets, such events could have had an impact. In order to fully comprehend this possible impact, we examine prices fluctuations in three dimensions: the observation time, the space dimension – the same underlying asset can be traded simultaneously in two different places – and the maturity of the transactions. We first focus on the efficiency of the shocks propagation: does it improve during crises? Then we concentrate on the paths of shocks propagation: are they modified? How? Finally we focus on the centrality of the prices system: does it change? Does it increase?.

We examine the impact, on commodity derivative markets, of two financial crises: the Subprime crisis and the bankruptcy of Lehman Brothers. These crises are "external" for commodity markets: they appeared in the financial sphere. Still, because now commodity markets are highly integrated, between themselves and with other financial markets, such events could have had an impact. In order to fully comprehend this possible impact, we examine prices fluctuations in three dimensions: the observation time, the space dimension – the same underlying asset can be traded simultaneously in two different places – and the maturity of the transactions. We first focus on the efficiency of the shocks propagation: does it improve during crises? Then we concentrate on the paths of shocks propagation: are they modified? How? Finally we focus on the centrality of the prices system: does it change? Does it increase?.