CREATE TABLE "interval_size" (
  "interval_name" text,
  "size_steps" real,
  "size_cents" real,
  "just_ratio" text,
  "just_cents" real,
  "error" text
);

Question: Tell me the average size for minor third
SQL: SELECT AVG("size_steps") FROM "interval_size" WHERE "interval_name"='minor third';