user: Question: What is the Margin of Victory, when Tournament is Mercedes Championships (3)?
Columns: ['Date', 'Tournament', 'Winning score', 'Margin of victory', 'Runner(s)-up']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['16 Mar 1997', 'Honda Classic', '−14 (68-68-67-71=274)', '1 stroke', 'Michael Bradley , Payne Stewart']
SQL:

assistant: SELECT "Margin of victory" FROM "Table" WHERE "Tournament" = 'Mercedes Championships (3)';