ground-truth

Ground truth refers to the accurate and reliable information that is known to be true and serves as a reference point for comparison with other data. In various fields such as remote sensing, geology, cartography, and machine learning, ground truth data is used to validate, calibrate, or improve the accuracy of models, algorithms, or predictions. This data is usually collected through direct observation, measurement, or survey, and is considered as the most reliable source of information for decision-making and analysis.