Evidence row 68089

What was observed

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  "name": "polls.karbach.digital",
  "owner_address": "0x6d8444caed95d9155785da10ac00247948957d61",
  "raw": {
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    ],
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    "extensions": {
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                    "best_mae": 0.42,
                    "institute": "Institut Wahlkreisprognose",
                    "mean_mae": 1.06,
                    "n_endpolls": 19,
                    "sd_mae": 0.38,
                    "worst_mae": 2.13
                  },
                  {
                    "best_mae": 0.43,
                    "institute": "Forschungsgruppe Wahlen",
                    "mean_mae": 1.2,
                    "n_endpolls": 34,
                    "sd_mae": 0.58,
                    "worst_mae": 2.92
                  }
                ],
                "elections_in_backtest": 34,
                "explanation": "accuracy_final_polls: mean absolute error of each institute's last poll before past elections. house_effects_points: average deviation per party versus the o...",
                "house_effects_points": {
                  "Forschungsgruppe Wahlen": {
                    "AfD": -0.65,
                    "CDU": -2.15,
                    "Grüne": -1.3,
                    "Linke": 2.42,
                    "SPD": 1.9
                  },
                  "INSA": {
                    "AfD": 0.8,
                    "CDU": -2.33,
                    "Grüne": -4.43,
                    "Linke": 3.53,
                    "SPD": 3.1
                  },
                  "Infratest dimap": {}
                },
                "model_weights": {
                  "Forschungsgruppe Wahlen": 1.07,
                  "INSA": 0.7,
                  "Infratest dimap": 1.24
                }
              },
              "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...",
              "project": "Ein Projekt von Karbach.Digital (https://karbach.digital)",
              "source": {
                "polls": "dawum.de",
                "polls_license": "ODbL 1.0",
                "polls_license_url": "https://opendatacommons.org/licenses/odbl/1-0/",
                "processing": "polls.karbach.digital (Max Karbach)"
              },
              "uncertainty": null,
              "updated_at": "2026-10-18 04:30:24"
            },
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          }
        },
        "schema": {
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          "required": [
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          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-10-18T14:02:39.825Z",
    "quality": {
      "l30DaysTotalCalls": 1,
      "l30DaysUniquePayers": 1,
      "lastCalledAt": "2026-10-18T14:02:39.639Z"
    },
    "resource": "https://api.polls.karbach.digital/v1/institutes",
    "serviceName": "polls.karbach.digital",
    "tags": [
      "elections",
      "germany",
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      "politics",
      "bundestag"
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    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Polling institutes: accuracy of final polls in past elections and average bias per party. Use when asked which German polling institute is most accurate or biased. Source-attributed, German data, updated every six hours."
}

What the leaf hashes

{"body":"6b85b3e19404445122a9c989a6a5e919d1dcfdeda6c40f88411734d4e11d3e49","id":68089,"kind":"listing","method":"baseline/1","observed_us":1793025466167510,"prev":null,"subject":"x402_bazaar:https://api.polls.karbach.digital/v1/institutes","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-10-26 (296695 rows).

1. 0x81db74d0d8e8c2f4a2f5165252478813812a6bdf8fa0aed35ee8a853f2741d58
2. 0x684272b7a36cea26ced84785d58cef799d5499051a1a78a854db1a8e53eebad1
3. 0x5c24a836a87db98b63561b6f43098158ace1d0bbf6d0bdc73e8fff97cf764789
4. 0x32d88dc0c0dc0b5f134b76cfd6236b96622a967bb6721c802823073012e84a54
5. 0x55fdc7a8b1ea046cad85b9a1b534d64615b576633d2e6c628e27130372339c6b
6. 0x870bd3a328da44714a8c42fb4a8e8cc860d96708923a3442da29c4b89a8b5fd3
7. 0xd569c2a3f9287c5c83556a2814857d91dfea9e7014193fd5b16ecd0363506d2e
8. 0x37cd26abd806c53dc8a5b17b26c9bdea69fdaaa1a04da87b8441fe2265cd8172
9. 0xbe47ad1982ff0fb785a097b90b6d278f04696940c378207e7547167cf5704d80
10. 0xbdc4a4c8cadfe346c042615305bf6ada497fa5128db30e977a80cb6245a189d3
11. 0xb998e012b473bde18346485cd0b7b8b31ab48d5f22ba9bc660bb2e523161e255
12. 0x08155d70132f82e370214fc5b72194dfa6f5e57670b7bcf74776e8418302897e
13. 0x4d2ee986a690e903126f449b4e9e62d5572b350357ab4496a83488949b131c29
14. 0x0eff463856b0992d53ab7d8c0b97c71541413358bdd445710c1e4b6aeb4d8f78
15. 0x7eb603d37f0f22dae1ea013e391889906ffc0139ff26e25b044bee38eec8f9b2
16. 0x2b6e23e3624a1b66e1d2298cfbce99a93ce6b13d24a58112a71802d79c5f7a76
17. 0xd21942ae3214eff88e08ab04884fd4b11958b51af9a0741b7668e2d07a2c56c9
18. 0x9a9024edb5069d88a324facb310a5ce8e495214bbaa968f077bede437390194f
19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a

Day root

0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8

Chained

0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a

Published

On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae