About original_crowdsourced_data. 

Table structure:
 
"userid"    - a unique user identifier         
"validation_id"    - a unique submition identifier  
"timestamp"    - submition time      
"submission_item_id" - a unique submition item (question asked) identifier
"pixel_center_x"    - x coordinate of a 100m x 100m pixel 
"pixel_center_y"   - y coordinate of a 100m x 100m pixel  
"enhancement"     - a unique idenetifier for a combination of a question asked and a given answer   
"skip_reason"  - a skip reason: 1-no image/low resolution/clouds; 2- too difficult; 5- no forest
"comment"    - a comment (text field)        
"name"        - a question asked       
"name.1"     - an answer to the question        
"sample_id" - a unique location (100m x 100m pixel) identifier