This preliminary product contains annual land cover, land use, and change process variables for reference data plots in a .csv table. The same information available in the.csv file is also provided in a .xlsx format. The LCMAP Preliminary Duplicate Attributes Collection for Reference Data includes the attributes collected from 30-meter by 30-meter plots across the conterminous United States (CONUS) that were randomly selected during data collection to have 2 independent interpretations. These duplicate interpretations were utilized in the quality assurance and quality control processes for the creation of the final, authoritative LCMAP Reference Data Product. These attributes were collected via manual image interpretation. The interpretations collected variables related to primary and secondary land use, primary and secondary land cover(s), change processes, and other ancillary variables annually across CONUS from 1984-2016. The duplicate interpretations were utilized to identify classes and situations that could require additional interpreter training, further quality review, and/or correct identified errors in the preparation of the final dataset. The data in this dataset is considered interim/provisional in nature. The LCMAP Preliminary Duplicate Attributes Collection for Reference Data provides the interpretation attributes for a subset of the 25,000 plots that were utilized for evaluation and validation of the Land Change Monitoring, Assessment, and Projection (LCMAP) land cover and land cover change products.