Panel data framework has often been used to build early warning systems for financial crises. This paper questions the implicit assumption that crises are homogenously caused by identical factors. It suggests a preliminary step aiming at forming optimal country clusters.
van den Berg, J. J. F., Candelon, B., & Urbain, J. R. Y. J. (2008). A cautious Note on the Use of Panel Models to Predict Financial Crises. Economics Letters, 101(1), 80-83. https://doi.org/10.1016/j.econlet.2008.06.015