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Methodology

Validation & Transparency

What we test, what we can't test yet, and what we're honest about.

Postcodes

3,193

scored

Structural

11

indicators per postcode

Exposure

6

domains

Signals

20+

automated sources

Coverage

WA + NSW

station-level, national for other signals

What's Validated

The scoring engine underneath the exposure profiles has been validated against five quantitative tests. We chose to present profiles instead of scores because a profile is more actionable but the validated methodology is what gives those profiles their grounding.

Normalisation Robustness

Validated

Min-max vs percentile-rank normalisation compared across all postcodes. Method choice does not change rankings.

BRIC rank correlation (Spearman)

0.976

threshold: 0.85 met

INFORM rank correlation (Spearman)

0.952

threshold: 0.85 met

Rankings are robust to the choice of normalisation method. Both scoring frameworks remain highly correlated regardless of whether min-max or percentile-rank normalisation is used.

Weight Sensitivity

Validated

Indicator weights perturbed by +/-20%. Stable under parameter uncertainty.

Min BRIC rank correlation

0.999

threshold: 0.90 met

Min INFORM rank correlation

0.996

threshold: 0.90 met

Max quadrant change rate

9.1%

threshold: 10% met

Perturbation rounds

4

Even at maximum perturbation (+/-20% on all indicators simultaneously), fewer than 1 in 10 postcodes change classification. The structural data is stable under parameter uncertainty.

External Validation (SEIFA)

Validated

Structural data correlated with the ABS Socio-Economic Index for Areas (SEIFA IRSD). Validates that structural indicators capture genuine socioeconomic patterns.

Pearson r

0.909

threshold: 0.40 met

Spearman rho

0.912

threshold: 0.40 met

Postcodes compared

2,624

Strong correlation with SEIFA IRSD validates that our structural data captures genuine socioeconomic patterns. The gap between r=0.91 and 1.0 is the point: perfect correlation would mean the two measures are identical and one is redundant. The CRI captures dimensions SEIFA does not, particularly diversity and crisis exposure.

Diversity Weighting

Validated

Compares standard and diversity-weighted scoring across mining-dependent postcodes. Concentrated economies are correctly flagged.

Standard vs diversity Spearman

0.997

Mining postcodes scoring lower

22 / 28

threshold: majority met

Diversity weighting reveals structural brittleness that standard scoring misses. Communities with concentrated economies appear resilient on volume-based indicators but are exposed when diversity is weighted. 22 of 28 mining-dependent postcodes score lower under diversity weighting, consistent with the hypothesis that concentration mimics resilience but creates systemic fragility.

Exposure Profile Validation

The exposure profile maps structural characteristics to exposure domains using deterministic rules. Here is what we can verify and what we cannot.

What Can Be Verified

Auditable

Deterministic rules, reproducible outputs, verifiable positions.

Exposure rules are deterministic and auditable

Every exposure mapping is a deterministic function of structural inputs. No randomness, no LLM inference. You can inspect the code to trace any exposure rating back to its inputs.

Signal contextualisation uses parameterised templates

When signals are contextualised for a postcode, the text is generated from parameterised templates with known inputs. Reproducible, not generative.

Structural characteristics match against national percentiles

Every structural characteristic is positioned against the national distribution. You can verify your community's position against the ABS source data.

What Cannot Be Validated Yet

Honest gap

Limitations we name openly rather than hide.

Cascade timeline estimates are structural, not empirical

Timeline estimates (e.g. 'fuel price increases reach grocery shelves in 2-4 weeks') are based on industry knowledge and published cost coefficients, not empirical measurement of actual propagation delays. We present them as estimates, not forecasts.

Exposure mapping rules are based on domain expertise, not statistical derivation

The rules that map structural characteristics to exposure domains are authored from domain expertise, not derived from statistical models. This is a deliberate design choice: transparent rules that anyone can inspect and challenge are more trustworthy than an opaque model with higher accuracy claims.

Station availability gap detection is a proxy

When fuel station reporting gaps are used as a demand pressure signal, it is a proxy measure. Stations may stop reporting for operational reasons unrelated to supply pressure. We flag this uncertainty in the signal context.

Data Transparency

We show what data is available and name what is missing. Every data point is sourced and dated.

What We Disclose

Transparent

Data provenance, age, and coverage gaps are surfaced, not hidden.

Most structural data is from 2021 Census (5 years old)

We say so on every profile. The 2026 Census will allow us to refresh structural indicators. Until then, the data reflects 2021 conditions and we are explicit about that.

Signal availability varies by state

WA has the most transparent fuel data (FuelWatch, station-level, daily). NSW provides data via CKAN and FuelCheck. Other states have limited or no automated public data. We surface what is available and name what is missing.

Every data point is sourced and dated

Structural characteristics show their data source and vintage. Live signals show their fetch timestamp and source authority. Derived signals like cascade pressure are labelled as estimates.

Missing data is named, not hidden

When an indicator has no data for a postcode, we show that gap rather than imputing a value or hiding the field. When a signal source is unavailable for a region, we say so.

OECD 10-Step Compliance

The scoring engine follows the OECD/JRC Handbook on Constructing Composite Indicators (2008) and the England BRIC adaptation by Camacho et al. (2024), which achieved 100% OECD compliance and is the closest methodological precedent. We preserve this rigour even though the primary output is now an exposure profile rather than a composite score.

StepRequirementStatus
1Theoretical frameworkCompleteDROP model + INFORM + coherence/entrainment lens
2Data selectionComplete11 structural indicators with documented rationale
3Imputation of missing dataCompleteMissing data handling with explicit gap surfacing
4Multivariate analysisCompletePCA + Cronbach alpha per capital
5NormalisationCompleteMin-max + percentile-rank, robustness validated
6Weighting and aggregationCompleteEqual weighting within capitals, sensitivity tested
7Robustness and sensitivityCompleteNormalisation robustness + weight perturbation analysis
8Back to the dataCompleteFull decomposition in exposure profiles
9Links to other indicatorsCompleteSEIFA IRSD external validation (r=0.909)
10VisualisationCompleteExposure profiles, signal cascade, action templates

Validation run: 20 March 2026. Source data: ABS Census 2021, SEIFA 2021, MMM 2023, CER postcode data. Signal sources: WA FuelWatch, AIP terminal gate prices, AEMO, RBA, ABS SDMX, DCCEEW, Yahoo Finance.