WHich Tournament venue has a Tournament Champion of duke and a Record of 15–1?
CREATE TABLE "champions_by_year" (
  "year" text,
  "regular_season_champion_s" text,
  "record" text,
  "tournament_champion" text,
  "tournament_venue" text,
  "tournament_city" text
);
SELECT "tournament_venue" FROM "champions_by_year" WHERE "tournament_champion"='duke' AND "record"='15–1';