I wanted a cross-venue price comparison for prediction markets and assumed the hard part would be the order books. It was not. The hard part is deciding that two markets are the same market. One event, two records, nothing in common The Federal Reserve decision at the 16 September 2026 meeting. On Polymarket it is titled Fed Decision in September? at slug fed-decision-in-september-762 . On Kalshi it is titled Fed funds rate after Sep 2026 meeting? under ticker KXFED-2...