Automatic machine learning of empirical models from experimental data has
recently become possible as a result of increased availability of computational
power and dedicated algorithms. Despite the successes of non-parametric
inference and neural-network-based inference for empirical modelling, a
physical interpretation of the results often remains challenging. Here, we
focus on direct inference of governing differential equations from data, which
can be formulated as a linear inverse problem. A Bayesian framework with a
Laplacian prior distribution is employed for finding sparse solutions
efficiently. The superior accuracy and robustness of the method is demonstrated
for various cases, including ordinary, partial, and stochastic differential
equations. Furthermore, we develop an active learning procedure for the
automated discovery of stochastic differential equations. In this procedure,
learning of the unknown dynamical equations is coupled to the application of
perturbations to the measured system in a feedback loop. We demonstrate with
simulations that the active learning procedure improves the inference of
empirical, Langevin-type descriptions of stochastic processes.