humanannotated

Human-annotated data refers to data whose labels and markings are produced by human annotators rather than by automated systems. In supervised learning, such data provides ground truth labels used to train and evaluate models. The annotations describe objects, actions, or properties within the data and can range from coarse labels to detailed markup.

Common forms of human annotation occur across domains. In image data, annotators may provide object labels, bounding boxes, or pixel-level segmentations. In text, they may assign part-of-speech tags, named entities, sentiment, or discourse structure. In audio, annotators may generate transcripts, speaker labels, and timing information. To ensure usefulness, projects typically accompany annotations with guidelines that define acceptable interpretations and formats.

Creation and quality control are central considerations. Annotations are often produced through crowdsourcing or by domain experts. Quality control methods include clear guidelines, multiple annotators per item, measures of inter-annotator agreement, and adjudication against gold-standard references. Techniques such as active learning help reduce labeling effort by prioritizing the most informative items. Privacy, consent, and data provenance are important ethical considerations when annotations involve sensitive information.

Applications abound in machine learning and data science. Human-annotated data underpins model training, evaluation, and benchmarking across computer vision, natural language processing, speech recognition, medical imaging, and social science research. While highly accurate for nuanced judgments, human annotation can be costly and may introduce subjectivity or bias if guidelines are incomplete or inconsistently applied.