As my study goes into somewhere with more statistical flavor, I would like to share a powerful tool that I learned by chance.
To study a complicated system, the data-driven approach focuses on the data. From analyzing the data, scientists try to make observations, discover patterns and regularities, draw conclusions, and so on. Then, scientists want to use these findings to make prediction. This approach is different from the physics-based methods, where people try to deduct/simulate the system behavior from some clearly defined principles.