“…It is often seen as " (i) a diverse collection of high-dimensional models for statistical prediction, combined with (ii) so-called 'regularization' methods for model selection and mitigation of overfit, and (iii) efficient algorithms for searching among a vast number of potential model specifications" (Gu et al, 2020). Mostly one of the following methods is well suited to address the three challenges mentioned earlier: linear models for regression (including regularization via shrinkage methods with penalization, such as Ridge Regression, Lasso, or Elastic Nets), dimension reduction via principal components regression and partial least squares, regression trees and forests (including boosted trees and random forests), (deep) neural networks, and boosting (Oztekin et al, 2016;Athey & Imbens, 2019;Coulombe et al, 2020;Gu et al, 2020;Hiabu et al, 2020;Iworiso & Vrontos, 2020;Wu et al, 2020;Gambella et al, 2021).…”