user: Question: Which Margin of victory has a Runner(s)-up of Dave Barr?
Columns: ['Date', 'Tournament', 'Winning score', 'Margin of victory', 'Runner(s)-up']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Apr 29, 1984', 'Houston Coca-Cola Open', '–10 (70-68-68-68=274)', '1 stroke', 'Buddy Gardner']
SQL:

assistant: SELECT "Margin of victory" FROM "Table" WHERE "Runner(s)-up" = 'Dave Barr';