{"uid":"cap_rdsPHB5H9U26GCy5YkQTm","slug":"polls-karbach-digital-track-record-9af41ece","name":"polls.karbach.digital Track Record","description":"Frozen forecasts versus official results, 2026 out of sample and 34-election backtest. Use when asked how reliable these forecasts were in past elections. Source-attributed, German data, updated every six hours.","url":"https://api.polls.karbach.digital/v1/track-record?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"properties":{"type":"string"}}},"responseSchema":{"type":"json","example":{"data":{"description":"Forecasts frozen eight days before the election, measured against official results.","summary_2026":{"mae":2.17,"slots":21,"sieger":3,"wahlen":3,"im_band":17},"elections_2026":[{"eid":"st-2026","mae":2.47,"date":"2026-09-06","name":"Landtagswahl Sachsen-Anhalt","actual":{"AfD":43.8,"BSW":5.3,"CDU":17.2,"FDP":2.6,"SPD":9.3,"Linke":8.6,"Grüne":8.9},"im_band":5,"parteien":7,"v4_frozen":{"AfD":42.3,"BSW":4.1,"CDU":22.1,"FDP":3.3,"SPD":7.3,"Linke":12,"Grüne":5.3},"frozen_date":"2026-08-28","sieger_stimmt":true},{"eid":"be-2026","mae":1.74,"date":"2026-09-20","name":"Abgeordnetenhaus Berlin","actual":{"AfD":16.3,"BSW":4.7,"CDU":18.8,"FDP":2.5,"SPD":12.1,"Linke":25.7,"Grüne":14.3},"im_band":7,"parteien":7,"v4_frozen":{"AfD":18,"BSW":3.8,"CDU":19.9,"FDP":3.3,"SPD":12.5,"Linke":20.2,"Grüne":16.1},"frozen_date":"2026-09-11","sieger_stimmt":true}],"backtest_34_elections":{"mae":1.27,"brier":0.0711,"ci95_hit":96.9,"n_wahlen":34,"updated_at":"2026-10-18 04:30:24","methodology":"v4.16 — punkt=weighted-poll-avg-fenster5 (CLR-sim nur fuer verteilung/CI/sitze/koalitionen; ablation A6/A7 2026-06-10) + per-partei-sigma + party-correlation...","winner_total":34,"winner_correct":31,"baseline_poll_avg_5_mae":{"n":34,"mean_mae":1.3}}},"docs":"https://api.polls.karbach.digital/v1/","model":null,"notice":"Scenario analysis based on published opinion polls. Not a prediction and not a voting recommendation. Coalitions are arithmetic majorities only, not statemen...","source":{"polls":"dawum.de","processing":"polls.karbach.digital (Max Karbach)","polls_license":"ODbL 1.0","polls_license_url":"https://opendatacommons.org/licenses/odbl/1-0/"},"project":"Ein Projekt von Karbach.Digital (https://karbach.digital)","updated_at":"2026-10-18","uncertainty":null}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_IvPyy543Uz2Alz_Rboz_u","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the validated backtesting track record of a German election Monte-Carlo forecast model, including MAE, winner accuracy, and per-election results calibrated against 34 historical elections.","exampleAgentPrompt":"Pull the track record for the Karbach German election Monte-Carlo model — I want to see its historical MAE, how often it picks the correct winner, and the 95% confidence interval hit rate across the 34 backtested elections.","exampleUseCases":[{"title":"Validating German election forecast accuracy","prompt":"What is the overall accuracy of the Karbach German election simulation model? I want the MAE, winner prediction rate, and CI hit rate from the full 34-election backtest."},{"title":"Comparing 2026 state election forecasts to real results","prompt":"Show me how the Karbach German election model performed on the 2026 elections — specifically the frozen forecasts versus the actual results for each Landtag election and the Berlin Abgeordnetenhaus."},{"title":"Assessing model methodology before relying on its forecasts","prompt":"Before I use the Karbach polls simulation for a political analysis piece, can you fetch its track record so I can see its methodology version, Brier score, and how it compares to a simple 5-poll average baseline?"}],"resultDescription":"A JSON object containing: a backtest summary over 34 historical German elections (MAE ~1.27, Brier score, 95% CI hit rate, winner accuracy), a 2026 election summary with per-election frozen forecasts versus official results, methodology description, data source attribution (dawum.de, ODbL 1.0), and a last-updated timestamp. Forecasts are frozen 8 days before each election and compared against official results.","failureModes":["HTTP 402 if payment header is missing or malformed (x402 micropayment required)","Stale data if the 6-hour update cycle hasn't completed yet","Empty elections_2026 array if no 2026 elections have concluded yet","Network timeout if the API server is temporarily unavailable"],"whenToPreferThis":"Use this endpoint when you need to assess the credibility and historical accuracy of the Karbach German election Monte-Carlo model before relying on its forecasts, or when you need to cite validated model performance metrics (MAE, Brier, CI hit rate) in a political analysis context. Prefer it over raw forecast endpoints when the question is about model quality rather than a specific upcoming election.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-28T12:39:31.463Z","isFirstParty":false,"canonicalSlug":"polls-karbach-digital-track-record-9af41ece"}