Explainable Artificial Intelligence (XAI): What we know and what is left to attain Trustworthy Artificial Intelligence

Sajid Ali, Tamer Abuhmed, Shaker H. Ali El-Sappagh, Khan Muhammad, Jose Maria Alonso-Moral, Roberto Confalonieri, Riccardo Guidotti, Javier Del Ser, Natalia Díaz Rodríguez, Francisco Herrera

Abstract: Highlights•A novel four-axis framework to examine a model for robustness and explainability.•Formulation of research questions at each axis and its corresponding taxonomy.•Discussion of different explainability assessment methods.•A novel methodological workflow for determining the model and explainability criteria.•Revisited discussion on challenges and future directions of XAI and Trustworthy AI.