ALANNO: An Active Learning Annotation System for Mortals

In today's data-driven society, supervised machine learning is rapidly evolving, and the need for labeled data is increasing. However, the process of acquiring labels is often expensive and tedious. For this reason, we developed ALANNO, an open-source annotation system for NLP tasks powered by active learning. We focus on the practical challenges in deploying active learning systems and try to find solutions to make active learning effective in real-world applications. We support the system with a wealth of active learning methods and underlying machine learning models. In addition, we leave open the possibility to add new methods, which makes the platform useful for both high-quality data annotation and research purposes.