Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 192-198). Also available on the Internet.

Thesis (M.B.A.)--University of Hong Kong, 1984.

Thesis (M. Phil.)--University of Hong Kong, 1987.

Thesis (M.B.A.)--University of Hong Kong, 1981.

Thesis (M.B.A.)--University of Hong Kong, 1987.

published_or_final_version / Law / Doctoral / Doctor of Philosophy

published_or_final_version / Statistics / Master / Master of Social Sciences

In late 1994 when the Mexican financial crisis occurred, many emerging economies experienced negative returns. For instance, Latin American markets, Hong Kong, Singapore, Korea and Thailand all showed stock price declines of 15% to 30%. Similarly, the Asian Crisis of 1997, the Russian Crisis of 1998, and the Brazilian Crisis of 1999 have all brought about significant negative returns in many seemingly unrelated emerging markets. Based on these figures, it was found worthwhile to study the spread of financial crises among international stock exchanges, in a quest to reach clues on &lsquo / contagious volatility&rsquo / . This study aims to analyze the nature and spread of international financial crises. Remaining within its scope, the study on contagion of volatility studied 72 positive and negative events and reached the conclusion that markets move together in times of crisis, with outstanding increases in their correlations. This finding shows that the benefits of international diversification are reduced because of increasing correlations among markets during events. Another striking finding was that, though at a lesser extent, the same co-movement was observed with upturns in markets. It was also observed that volatility tends to be higher within periods of negative and positive events analyzed in the study. As country groups that move together in crisis periods were analyzed, it seemed that economic and trade linkages were an influencing factor in their behavior. In the light of these findings, the possible mechanisms of the spread of contagion and policies that could be implemented to withstand it were discussed.

The understanding of the emergent behaviour of complex systems is probably one of the most intriguing challenges in modern theoretical physics. In the present Thesis we use novel data analysis techniques and numerical simulations in order to shed some light on the fundamental mechanisms involved in their dynamics. We divide the main core of the research into three parts, each of which address a specific, and formally well defined, issue. In the first part, we study the processes of self - organization and herding in the evolution of the stock market. The data analysis, carried out over the fluctuations of several international indices, shows an avalanche - like dynamics characterized by power laws and indicative of a critical state. Further evidence of criticality relates to the behaviour of the price index itself. In this case we observe a power law decline with superimposed embedded log - periodic oscillations which are possibly due to an intrinsic discrete scale invariance. A stochastic cellular automata, instead, is used to mimic an open stock market and reproduce the herding behaviour responsible for the large fluctuations observed in the price. The results underline the importance of the largest clusters of traders which, alone, can induce a large displacement between demand and supply and lead to a crash. The second part of the Thesis focuses on the role played by the complex network of interactions that is created among the elementary parts of the system itself. We consider, in particular, the influence of the so - called " scale - free " networks, where the distribution of connectivity follows a power law, on the antiferromagnetic Ising model and on a model of stochastic opinion formation. Novel features, not encountered on regular lattices, have been pointed out. In the former case a spin glass transition at low temperatures is present while, in the latter, the turbulent - like behaviour emerging from the model is found to be particularly robust against the indecision of the agents. The last part is left for a numerical investigation of an extremal dynamical model for evolution / extinction of species. We demonstrate how the mutual cooperation between them comes to play a fundamental role in the survival probability : a healthy environment can support even less fitted species. / Thesis (Ph.D.)--School of Chemistry and Physics, 2006.

Thesis (D.B.A.) -- University of Western Sydney, Nepean, 2001. / Thesis submitted for the degree of Doctor of Business Administration, University of Western Sydney, Nepean, 2001. Includes bibliographical references.