Why big data? -- Neural networks in finance -- Supervised models -- Semi-supervised learning -- Letting the data speak with unsupervised learning -- Big data factor models -- Data as a signal versus noise -- Applications : big data in options pricing and stochastic modeling -- Data clustering.

Bid and ask sizes at the top of the order book provide information on short-term price moves. Drawing from classical descriptions of the order book in terms of queues and order-arrival rates (Smith et al., 2003), we consider a diffusion model for the evolution of the best bid/ask queues. We...