{"success":true,"engine":"Black Belt Labs","metric_id":"M10052","name":"Cardinality Frontier Distance","category":"personal","classification":"classic","update_frequency":"hourly","inputs":["Other public data"],"inputs_are":"types of input","lookback_windows":[],"lookback_basis":null,"formula":"Personal: gap between the portfolio's trailing 60d Sharpe and the best Sharpe achievable holding AT MOST 3 assets from the investable set. Cardinality-constrained Markowitz is NP-hard classically. QC-candidate: QUBO; classical enumeration today.","formula_published":true,"definition_version":"1.0","definition_history":[{"version":"1.0","effective_from":"2026-09-11T09:07:49Z","change_note":"initial recorded definition"}],"methods":["progr","quant-hw","quant-sim"],"disclaimer":"Madjik metrics are informational market indicators computed by Black Belt Labs. They are not investment advice, an offer, or a recommendation to buy or sell any asset."}