
Classifying market states
Typically, we cannot predict a meaningful portion of daily or higher-frequency market returns. A more realistic approach is classifying the state of the market for a particular day or hour. A powerful tool for this purpose is artificial neural networks. This is a popular machine learning method that consists of layers of data-processing units, connections between them and the application of weights and biases that are estimated based on training data. Classification with neural networks is suitable for complex structures and large numbers of data points. A simple idea for a neural network approach to financial markets is to use combinations of price trends as features and deploy them to classify the market into simple buy, sell or neutral labels and to estimate the probability of each class at each point in time. This approach can, in principle, be extended to include trading volumes, economic data or sentiment indicators.