Forecasting market states

In common terminology, there are periods of'bull' market in which prices are more likely to rise and periods of'bear' market in which prices are more likely to fall. These different'states' of markets are commonly attributed in literature to unobservable, orlatent, regimes representing a set of macroeconomic, market and sentiment variables. Many time series models presented in literature tried to capture this phenomenon. Among the most popular methods, it is worth mentioning the TAR models (Tong 1978), trying to estimate'structural breaks' in the time series process, and the Markov Switching models (Hamilton 1989), where the change in regimes are parametrized by means of an unobserved state variable typically modelledas Markov chain. However, the application of TAR models in finance is frequently criticized since it cannot be established with certainty when a structural break has occurred in economic time series and the prior knowledge of major economic events could lead to bias in inference (Campbellet al. 1997). Markov switching models, on the other hand, are highly affected by the curse of dimensionality. In particular, for slightly more complex dynamics than the original proposal (Hamilton 1989), we need to rely on variational inference techniques or MCMC methods (Tsay 2005, Kim and Nelson 1999). This implies that, in a multivariate context and particularly if November 27, 2018 ForecastingMarketStates v2.1