user: Question: How many yards were averaged by the player that had a higher than 13 average with less than 18 long?
Columns: ['Player', 'Rec.', 'Yards', 'Avg.', "TD's", 'Long']
Types: ['text', 'real', 'real', 'real', 'real', 'real']
Sample row: ['Lawrence Samuels', 11.0, 116.0, 10.5, 1.0, 18.0]
SQL:

assistant: SELECT AVG("Yards") FROM "Table" WHERE "Long" < 18.0 AND "Avg." > 13.0;