Three Empirical Essays on Contemporary Issues in Finance

This cumulative thesis comprises three stand-alone papers: <br/>The first paper focuses on mergers and acquisitions in European and North American energy markets. By implementing an event study approach and analyzing the effects of proposed M&As on the stock returns of the involved companies as well as their competitors, conclusions are drawn on whether recent regulatory developments in both the EU and North America (i.e. legal and ownership unbundling) actually have the desired positive effects on market effciency. <br/>The second paper explores the possible investment portfolio diversification benefits of Bitcoin, a popular unregulated digital currency. After highlighting how Bitcoin works, discussing what sets Bitcoin apart from traditional investment assets and explaining the biggest threats of a Bitcoin investment, a mean-CVaR approach and a backtesting technique are applied on the complete available time series of Bitcoin data to analyze whether optimal portfolios should include Bitcoin. <br/>The third paper deals with the subject of socially responsible investing. Via a modification of Markowitz' Portfolio Selection Theory to incorporate the social responsibility of assets into the investment decision making process, a three-dimensional capital allocation plane can be set up, allowing investors to customtailor their asset allocations with a view to their personal preferences <br/>regarding return, risk and social responsibility. Utilizing a simulation approach, the model is then applied to an empirical data set of over 9,400 international stocks, including the complete universe of social responsibility-rated stocks.