Reference data set used to validate the hybrid cropland map at 500m (Fritz, S. 2024)

This is a reference data set for validation of the hybrid cropland map at 500m resolution for the year 2019 (Fritz, 2024, map available here) Sampling design: random whithin areas of improvement, where the WorldCereal map is performing better (less errors) than the GLAD cropland map 2019.  Number of sample sites: 500 Method of data collection: visual interpreation of various sources of information, including very high resolution images and photos.  Tool for data collection: Geo-Wiki Fields: userid  - unique user identifier submissionid - unique submission identifier (multiple submissions per location were possible) sampleid - unique location identifier long_description - cropland classes:   > 0%-10%      > 10%-20%      > 20%-30%      > 30%-40%      > 40%-50%      > 50%-60%      > 60%-70%      > 70%-80%      > 80%-90%     > 90%-100%    no cropland       not sure geowiki_class - cropland classes translated in numeric categories:   1 - > 0%-10%     2 - > 10%-20%     3 - > 20%-30%     4 - > 30%-40%     5 - > 40%-50%     6 - > 50%-60%     7 - > 60%-70%     8 - > 70%-80%     9 - > 80%-90%     10 - > 90%-100%   0 - no cropland       101 - not sure centroid_x, centroid_y - centroid coordinates for each 500m x 500m pixel