What is the average against of Murrayfield, Edinburgh?
CREATE TABLE table_name_13 (
    against INTEGER,
    venue VARCHAR
)
SELECT AVG(against) FROM table_name_13 WHERE venue = "murrayfield, edinburgh"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: What is the average against of Murrayfield, Edinburgh? ### Input: CREATE TABLE table_name_13 (
    against INTEGER,
    venue VARCHAR
) ### Response: SELECT AVG(against) FROM table_name_13 WHERE venue = "murrayfield, edinburgh"