user: Question: Who was the skip when the stolen ends against was 13? 
Columns: ['Country', 'Skip', 'W', 'L', 'PF', 'PA', 'Ends Won', 'Ends Lost', 'Blank Ends F/A', 'Stolen Ends For', 'Stolen Ends Against', 'Shot %']
Types: ['text', 'text', 'real', 'real', 'real', 'real', 'real', 'real', 'text', 'real', 'real', 'real']
Sample row: ['Canada', 'Kevin Martin', 10.0, 1.0, 92.0, 43.0, 47.0, 33.0, '1/6', 11.0, 2.0, 88.0]
SQL:

assistant: SELECT "Skip" FROM "Table" WHERE "Stolen Ends Against" = 13.0;