Risk Score Methodology

1. Purpose

The ScoreView risk score is a composite indicator that summarises the complaint risk profile of a social landlord. It is intended to help housing professionals quickly identify landlords whose determination records suggest elevated or deteriorating complaint performance, and to contextualise a single landlord's position relative to sector peers.

The score is computed from published Housing Ombudsman determination data only. It does not incorporate regulatory inspection grades, self-reported performance data, or any information outside the Ombudsman's public corpus.

2. Eligibility threshold

A risk score is only computed for landlords with 10 or more closed determinations in the corpus. Landlords below this threshold have too few data points for the rate and trend components to be meaningful.

3. Score components

The four components are additive; the total (0 to 100) is the sum of all four. A high score in any one component contributes directly to the total without being masked by another component.

Maladministration rate0 to 40 points

min(40, mal_rate × 40)

The proportion of all closed determinations that resulted in a finding of maladministration or severe maladministration, scaled linearly to 40 points. A landlord where every determination was upheld would score 40; one where none were upheld scores 0.

Trend direction0 to 20 points

Deteriorating → 20 pts ; Stable → 10 pts ; Improving → 0 pts

The direction of the quarterly maladministration rate over the last six quarters, measured by ordinary-least-squares linear regression. A positive slope greater than 0.01 per quarter is classed as deteriorating (20 pts); a negative slope smaller than minus 0.01 is improving (0 pts); anything in between is stable (10 pts). Landlords with fewer than three quarterly data points are treated as stable.

Severity0 to 25 points

min(25, (severe_mal / total) × 25)

The proportion of determinations that carry a finding of severe maladministration specifically, scaled linearly to 25 points. This component penalises landlords that attract the Ombudsman's highest censure independent of overall maladministration volume.

Case volume0 to 15 points

min(15, 15 × min(1, ln(n + 1) / ln(200)))

Logarithmically scaled on total determinations (n) using the natural logarithm. A landlord with 200 or more determinations scores the full 15 points; one with 10 (the minimum threshold) scores roughly 4.6 points. Volume is included because a high maladministration rate across a large caseload represents greater systemic risk than the same rate across a handful of cases.

4. Risk bands

Band thresholds are fixed for model v1.0. They may be recalibrated in future versions as the corpus grows and sector baseline rates shift.

5. Worked example

The following uses illustrative data to show how the score is calculated step by step.

Illustrative Housing Association: 120 total determinations, 36 maladministration, 6 severe maladministration, quarterly trend deteriorating.

Result: Medium (score 48.83, band 26 to 50).

6. Data sources and update frequency

Risk scores are recomputed nightly from the ScoreView determination corpus, which is updated weekly from publicly available Housing Ombudsman records. A score reflects the state of the corpus at the time it was computed; the as-of date is shown alongside each score on landlord profile pages.

Quarterly trend data uses all available quarters in the corpus up to the most recent complete quarter. Partial (in-progress) quarters are excluded from the trend calculation — see the following section for the full rationale.

The canonical implementation lives in backend/app/services/risk_scores.py. This page documents that code; if the two ever disagree, the code is authoritative.

7. Trend slope input window

The composite score's trajectoryclassification (improving, stable, or deteriorating) is derived from an ordinary linear regression over the most recent complete quarters of the landlord's quarterly maladministration rate. The slope input window holds up to six complete quarters.

The calendar-current quarter is excluded from the slope input. Two effects compound here, and both relate to the data, not to ScoreView's ingestion cadence:

• The quarter is still in flight while it elapses, so any records dated inside it cover only a fraction of its eventual range.
• Housing Ombudsman determinations are typically published on a 30 to 60 day lag after the underlying case closes, so even at the end of a quarter a sizeable share of that quarter's records has not yet been published.

Including a partial quarter as the trailing input bucket would bias the regression toward “deteriorating” simply because that bucket undercounts records relative to earlier complete quarters. The exclusion is a property of the published corpus, not of ScoreView's ingestion: the determinations corpus is updated weekly, and the in-flight quarter is excluded even when the most recent published determination is one day old.

One consequence is that scores can shift on the first day of a new quarter, as the previously in-flight quarter joins the slope input. That shift reflects the publication cadence of the underlying data sources, not a model change. See docs/timeline_chart_audit_2026-06.md for the full audit that established this policy across every ScoreView timeline chart.

8. Limitations

• The score reflects the published determination record only. It does not account for complaints resolved before reaching the Ombudsman, self-assessment submissions, or RSH regulatory grades.
• Matching between determination records and landlord profiles uses a case-insensitive name match. Landlords with inconsistent or alias names may have incomplete coverage.
• The volume component means that large landlords can score higher than small landlords with identical rates. This is intentional, systemic risk scales with caseload, but users should consider rate and volume components separately when comparing landlords of different sizes.
• Scores below the 10-determination threshold are not computed and should not be inferred.

9. Disclaimer

The risk score is a research tool provided by ThinkTribal Ltd. It does not constitute regulatory assessment, legal advice, or a prediction of Housing Ombudsman or RSH enforcement action. Users should verify all information against original determination records before relying on it for any professional purpose.

ScoreView is independent of the Housing Ombudsman Service and is not affiliated with, endorsed by, or acting on behalf of any regulator.