Essays on Interlocking Directorates and Speculative Dynamics
This thesis is composed by four chapters which can be classified in two broad topics. The first and second chapters deal with the properties of the networks created by interlock- ing directorates, while the third and fourth chapters with the so-called Efficient Market Hypothesis. Connecting these two topics is the notion of a stylized fact (also called a universal property) which is not accounted for by the currently stablished theory. The first chapter shows that the existence of a very well connected dominant community is not explained by the traditional preferential attachment models. In addition, it is also shown that the patterns of accumulation of board positions by single individuals observed in empirical data cannot be explained by a simple random binomial procedure. An in depth analysis of a time framed interlocking directorates dataset from Spain is presented in order to argue that board linkages might have generated some kind of special conditions for lending that would not exist if based on economic criteria only. In addition, the effects of a new gender equality regulation are investigate to conclude that women are still under represented in the boards of directors, although an increase in their absolute number could be observed. Finally, surrogate linearity tests and microscopic (agent based) models are applied in order to explain the stylized facts not account for by the Efficient Market Hypothe- sis. More specifically, with respect to the class of microscopic models called Structural Stochastic Volatility models, it is shown that the introduction of inactive traders in- creases the model ability to explain the stylized facts. Additionally, taking advantage of this model contest, it is argued that a simulation horizon one allows a model to run in order to estimate its parameters higher than what was previously assumed in not necessary in order to compare different models.