{
  "title": "Rivers East Senate 2023 missing-polling-unit reconstruction",
  "published_at": "2026-10-04",
  "status": "investigative estimate; not a certified result",
  "scope": {
    "contest": "Rivers East Senate",
    "inec_code": "SD/094/RV",
    "election_date": "2023-02-25",
    "expected_polling_units": 3503,
    "irev_counted_polling_units": 2850,
    "modelled_missing_polling_units": 653,
    "irev_coverage_percent": 81.36
  },
  "method": {
    "linkage": "Exact polling-unit code across Senate, House of Representatives and Rivers governorship result sheets transcribed from IReV.",
    "registered_voters": "Use agreeing House/governorship records, then single-source exact-PU values; material conflicts are discarded and imputed from the ward.",
    "accredited_voters": "Use same-day House accreditation where available; otherwise apply the ward aggregate accredited-to-registered rate, with an LGA fallback.",
    "valid_votes": "Apply the quality-screened Senate valid-to-accredited rate at ward level, with an LGA fallback.",
    "party_votes": "Apply vote-weighted, quality-screened Senate candidate shares from the same ward, with an LGA fallback.",
    "quality_rules": [
      "exact source polling-unit linkage",
      "result-sheet identity match",
      "party sum matches stated total valid votes",
      "candidate-party sum equals stated valid votes",
      "no votes assigned to non-candidate parties",
      "plausible registered/accredited/valid hierarchy"
    ]
  },
  "recovery": {
    "registered_voters_direct_exact_pu": 547,
    "registered_voters_imputed_ward": 106,
    "accredited_voters_direct_house": 123,
    "accredited_voters_ward_rate": 457,
    "accredited_voters_lga_rate": 73,
    "party_share_ward": 579,
    "party_share_lga": 74,
    "senate_quality_share_polling_units": 1410,
    "senate_quality_turnout_polling_units": 1400
  },
  "estimated_missing_polling_units": {
    "registered_voters": 358410,
    "accredited_voters": 76979,
    "valid_votes": 71302,
    "turnout_percent": 21.48
  },
  "estimated_tally": [
    {"rank": 1, "party": "LP", "irev_count": 93191, "estimated_missing": 25164, "estimated_full": 118355},
    {"rank": 2, "party": "PDP", "irev_count": 80148, "estimated_missing": 27186, "estimated_full": 107334},
    {"rank": 3, "party": "APC", "irev_count": 37258, "estimated_missing": 12071, "estimated_full": 49329},
    {"rank": 4, "party": "ADC", "irev_count": 8349, "estimated_missing": 827, "estimated_full": 9176},
    {"rank": 5, "party": "SDP", "irev_count": 5421, "estimated_missing": 2649, "estimated_full": 8070},
    {"rank": 6, "party": "APM", "irev_count": 3170, "estimated_missing": 269, "estimated_full": 3439},
    {"rank": 7, "party": "APP", "irev_count": 2823, "estimated_missing": 574, "estimated_full": 3397},
    {"rank": 8, "party": "ADP", "irev_count": 2542, "estimated_missing": 679, "estimated_full": 3221},
    {"rank": 9, "party": "NRM", "irev_count": 2468, "estimated_missing": 512, "estimated_full": 2980},
    {"rank": 10, "party": "ZLP", "irev_count": 1784, "estimated_missing": 264, "estimated_full": 2048},
    {"rank": 11, "party": "APGA", "irev_count": 1620, "estimated_missing": 427, "estimated_full": 2047},
    {"rank": 12, "party": "NNPP", "irev_count": 1817, "estimated_missing": 144, "estimated_full": 1961},
    {"rank": 13, "party": "A", "irev_count": 1440, "estimated_missing": 335, "estimated_full": 1775},
    {"rank": 14, "party": "YPP", "irev_count": 633, "estimated_missing": 201, "estimated_full": 834}
  ],
  "headline_comparison": {
    "irev_count_lp_minus_pdp": 13043,
    "estimated_missing_pdp_minus_lp": 2022,
    "estimated_full_lp_minus_pdp": 11021,
    "reported_declaration_pdp": 134283,
    "reported_declaration_lp": 74725,
    "reported_declaration_pdp_minus_lp": 59558
  },
  "sensitivity": [
    {"scenario": "ward shares; linked-data vote volume", "estimated_full_lp": 118355, "estimated_full_pdp": 107334, "lp_minus_pdp": 11021},
    {"scenario": "LGA shares; linked-data vote volume", "estimated_full_lp": 118490, "estimated_full_pdp": 108695, "lp_minus_pdp": 9795},
    {"scenario": "district shares; linked-data vote volume", "estimated_full_lp": 121773, "estimated_full_pdp": 108375, "lp_minus_pdp": 13398},
    {"scenario": "ward shares; observed votes per processed PU", "estimated_full_lp": 112813, "estimated_full_pdp": 101347, "lp_minus_pdp": 11466},
    {"scenario": "ward shares; all estimated accredited voters valid", "estimated_full_lp": 120359, "estimated_full_pdp": 109499, "lp_minus_pdp": 10860}
  ],
  "obio_akpor_house_coverage_check": {
    "expected_polling_units": 1211,
    "irev_counted_polling_units": 1167,
    "missing_polling_units": 44,
    "irev_coverage_percent": 96.37,
    "irev_count_lp": 67320,
    "irev_count_pdp": 36542,
    "irev_count_lp_minus_pdp": 30778,
    "estimated_registered_voters_missing": 32861,
    "estimated_accredited_voters_missing": 8383,
    "estimated_valid_votes_missing": 7669,
    "estimated_turnout_percent": 25.51,
    "registered_direct_exact_pu": 37,
    "registered_imputed_ward": 7,
    "accredited_direct_same_day_senate": 9,
    "accredited_estimated_house_ward_rate": 35,
    "required_registered_turnout_if_every_valid_vote_went_to_pdp_percent": 93.67,
    "shortfall_if_every_estimated_valid_vote_went_to_pdp": 23109
  },
  "limitations": [
    "IReV polling-unit counts are diagnostic observations, not certified collations.",
    "The model does not recreate cancellations, substitutions or the official collation chain.",
    "The reported numerical declaration was located as an INEC statement reported by news organisations, not as a complete declaration form for every candidate.",
    "Scenario checks are not statistical confidence intervals.",
    "Only INEC declares official election results."
  ]
}