Deleting Object Statistics
You can delete object statistics from the data dictionary. Except for testing purposes, this is usually not necessary. Nevertheless, it might happen that a table shouldn’t have object statistics because you want to take advantage of dynamic sampling (covered in Chapter 9). In that case, the following procedures are available in the dbms_stats package: delete_database_stats, delete_dictionary_stats, delete_fixed_objects_stats, delete_schema_stats, delete_table_stats, delete_column_stats, and delete_index_stats.
As you can see, for each gather_*_stats procedure, there is a corresponding delete_*_stats procedure. The former ones gather object statistics, and the latter ones delete object statistics. The only exception ...