Suchergebnisse

Over the past two decades, the Black Sea region has exhibited significantly growing wheat production and exports. In 2017/18, Russia ultimately became the world's largest wheat exporter, a position that was held by the USA for decades. Mostly serving destination markets in the Middle East and North Africa (MENA) region, Russian grain exports have become vital to ensuring regional and global food security. However, the Russian wheat export market shows several characteristics that can negatively affect agricultural trade, potentially jeopardizing food supply in import-dependent countries. First, in the face of severe harvest shortfalls, Russia and other Black Sea countries have frequently restricted grain exports in the past, which can contribute to price surges on international markets. Secondly, a functioning futures market reflecting Black Sea wheat does not yet exist. Grain traders therefore use established futures markets for price discovery and to hedge price risk in the Black Sea region, which can involve basis risk. Thirdly, previous research has suggested that Russian wheat exporters exercise market power in order to price discriminate among different destination markets. Further, grain exports can be hampered by deficiencies and bottlenecks in the Russian transportation and export infrastructure. Against this background, this dissertation analyzes how the ascent of Russian wheat exports changes the patterns of global physical trade, results in different pricing dynamics on physical and futures markets, and affects futures price volatility by changing trade policy. The methodological focus lies on time series econometrics, and price analysis in particular. Using vector autoregressive (VAR), autoregressive moving average (ARMA) and vector error correction models (VECM), the econometric analyses are conducted using price series recorded at varying frequencies (monthly to intradaily) to account for economic transactions occurring at different speed on physical compared to futures markets. An initial, descriptive analysis depicts the evolvement of Russian wheat exports over time, with respect to main destination regions. The focus on Russia's food trade with four key markets in the MENA region, namely Egypt, Turkey, Saudi Arabia and Iran, shows that grain trade is the central component in the respective trade ties. The deepening or loosening of food trade relations corresponds to the present state of respective political ties. Further, a market integration and price leadership analysis is conducted using a multivariate VECM approach. Analyzing the Egyptian wheat tender market as a proxy for the world wheat market, results suggest that European export prices play an increasingly important role for international wheat price formation, likely stemming from close regional proximity between European and Black Sea markets. These results are in line with the findings of a VAR analysis focusing on realized volatility relations between Black Sea spot and leading futures markets. Here, prices posted at the Euronext Paris (EPA) futures market are determined to affect the Black Sea physical market, while such an effect is not found concerning the Chicago Board of Trade (CBoT) market. Further, this analysis provides evidence of asymmetric adjustment to ruble jumps, which suggests that Russian wheat prices are more likely to increase in response to exchange rate movements than they are to decrease. The final ARMA analysis shows that news about Russian grain export restrictions significantly increase intraday seasonally adjusted realized volatility on the CBoT futures market. Further, elevated volatility can be determined in days preceding such news publications. These pre-announcement effects offer important insights into the validity of the Efficient Market Hypothesis (EMH) in the studied market. The restructuring of the world wheat market resulting from the rise of Russian wheat exports is ongoing. Particularly with respect to futures markets, leading exchanges still compete to establish a functioning Black Sea wheat futures contract that could potentially serve as novel global pricing benchmark. Moreover, the Russian government continues to intervene in the grain trade by imposing export taxes or quotas. Against the background of growing world populations and increased likelihood of harvest shortfalls due to climate change, it is stressed that unimpeded food trade is indispensable to ensure global food security. Policy recommendations aiming to prevent the introduction of food export restrictions are provided at the end of the dissertation.

AbstractWe examine the role of index futures trading in spot market volatility. We use the exponential generalized autoregressive conditional heteroskedasticity (EGARCH) approach to measure volatility, analyze causality and feedback relations between volatilities in the spot and futures markets, and test various hypotheses in the context of a multivariate model that incorporates other macrostate variables. Our empirical results suggest index futures trading may not be blamed for the observed volatility in the spot market. Rather, we find stronger and more consistent support for the alternative posture that volatility in the futures market is an outgrowth of a turbulent cash market. We use the regret (cognitive dissonance) theory to explain our results.