Unveiling the Financial Market: Data, Definitions, and Modeling Techniques

In this book, we will present and apply methods specifically designed to model the financial market, but, before starting to discuss the models, we need to make a brief introduction to the data that we will be working with. Our data consists on financial asset prices from several stock exchanges, with special attention to the New York Stock Exchange, the London Stock Exchange and the Lisbon Stock Exchange. Also, we focused on stock and forex (foreign exchange market) prices, because these present higher volatility and volume (i.e., more trades), and the data related to these assets is easier to obtain. Here, volatility is a statistical measure of the dispersion of returns for a given financial asset. It is often measured as either the standard deviation or variance between returns from that same asset. Moving further we will often use the terms "stock exchange" and "financial market" interchange-ably, but they slightly differ. The term "financial market" broadly refers to any marketplace where the trading of securities occurs, including the stock market, bond market, forex market, and derivatives market, among others, whilst the "stock exchange" is a facility where stockbro-kers and traders can buy and sell securities, such as shares of stock, bonds and other financial instruments. However, whenever we refer to the financial market we will be referring to the stock exchange.