TUDA-CCL at SemEval-2021 Task 1: Using Gradient-boosted Regression Tree Ensembles Trained on a Heterogeneous Feature Set for Predicting Lexical Complexity Sebastian Gombert author Sabine Bartsch author 2021-08 text Proceedings of the 15th International Workshop on Semantic Evaluation (SemEval-2021) Alexis Palmer editor Nathan Schneider editor Natalie Schluter editor Guy Emerson editor Aurelie Herbelot editor Xiaodan Zhu editor Association for Computational Linguistics Online conference publication gombert-bartsch-2021-tuda 10.18653/v1/2021.semeval-1.12 https://aclanthology.org/2021.semeval-1.12/ 2021-08 130 137