This document tracks post-V1 work to improve user value, predictive accuracy, forecasting reliability, and operational trust.
Add a comparables panel in Forecaster V1:- nearest/similar recent transactions,
- similarity score and distance explanation,
- comparable median/IQR for pricing sanity checks.
- Impact: improves user trust and practical decision support.
- Verify: user can explain prediction with comparables in one screen.
Add confidence/reliability score in prediction output:- based on data density, out-of-range flags, and segment error history.
- Impact: clearer decision risk awareness.
- Verify: confidence score decreases in sparse/OOD scenarios.
Add explicit alert rules:- out-of-distribution inputs,
- low sample support by town/flat segment,
- wide interval warning.
- Impact: prevents overconfident interpretation.
- Verify: alerts trigger on known edge-case profiles.
Add town/flat-type error slices frommetadata.jsondirectly in forecaster UI.Add model-card markdown generated per training run.Resolve MLflow vulnerability findings (upgrade to remediated release, re-audit).- Impact: closes known security risk in tracking stack.
- Verify:
pip-audit -r requirements.txtno longer reports known MLflow CVEs.
Add richer location and accessibility features (only with measurable gain):MRT network travel-time features,school-zone attributes,URA planning overlays.Impact: captures location premium more realistically.Verify: out-of-time MAE/RMSE improves vs current baseline.- Implementation note:
- official MRT references now sourced from data.gov.sg APIs,
- OneMap-based travel-time feature export added (
data/reference/mrt_travel_time_to_cbd.csv), - school/lifestyle premiums are currently delivered as explicit scenario overlays in UI (not yet trained as causal model coefficients).
Add leakage-safe lagged market features:rolling town/flat medians and liquidity indicators using strict historical cutoffs.Impact: better market-state representation.Verify: no future leakage in feature generation tests.
Add model blending experiments:tree model + comparables anchor blend,governed by holdout/backtest performance.Impact: stabilizes noisy point predictions.Verify: lower test RMSE without interval miscalibration.
Add rolling-origin backtests (multiple windows, not single holdout).Add interval calibration report (coverage by segment/time window).Add exogenous-aware forecasting ablations (rates/policy lags) with strict baseline comparisons.Impact: more realistic trajectory confidence and fewer false trends.Verify: calibration gap and backtest errors improve consistently.
- Add scenario simulator:
- vary transaction month, lease, floor area, and town assumptions,
- show delta impacts and uncertainty shifts.
- Impact: decision planning rather than static prediction lookup.
- Verify: scenario outputs are reproducible and explainable.
- Add segment-focused views:
- buyer mode (affordability/downside),
- seller mode (listing range),
- investor mode (yield + volatility + lease-risk profile).
- Impact: relevance across user intents.
- Verify: each mode exposes tailored KPIs and actions.
- Add drift report command:
- feature drift + residual drift since last training run.
- Add scheduled retraining with artifact version pinning.
- Add feedback-to-retraining pipeline:
- leverage user ratings + actual sale outcomes when available.
- Impact: continuous model improvement loop.
- Verify: retrain job produces signed artifact and changelog entry.
- Trajectory deep models (Prophet/LSTM) as optional experimental track only.
- Full model registry and approval gates (staging vs production) after stable pipeline maturity.
- Online serving API (FastAPI) with auth/rate-limits/audit logs only after usage justifies ops overhead.
- End-to-end automatic retraining triggers from live events remain deferred.
- Do not adopt deep-learning-first architecture before repeatable lift over tabular baselines.
- Do not broaden macro feature ingestion without out-of-time performance gains.
flowchart LR
uxTrust[UserTrustFeatures] --> dataQual[DataQualityAndLeakage]
dataQual --> featureLift[FeatureEngineeringLift]
featureLift --> modelEval[ModelAndBacktestRigor]
modelEval --> forecastEval[ForecastCalibration]
forecastEval --> opsLoop[FeedbackRetrainLoop]
- Deliverables:
- comparables panel,
- confidence score,
- OOD/sparsity/interval alerts.
- Acceptance criteria:
- prediction screen includes trust signals and contextual comparables,
- alerts fire correctly on known edge cases.
- Deliverables:
- location/accessibility feature set,
- strict lagged market features.
- Acceptance criteria:
- feature pipeline has no temporal leakage,
- measurable out-of-time error improvement.
- Deliverables:
- rolling-origin backtest module,
- interval calibration report by segment.
- Acceptance criteria:
- calibration/report artifacts generated per run,
- metrics are stable across windows (not one-off wins).
- Deliverables:
- scenario simulator,
- buyer/seller/investor mode dashboards.
- Acceptance criteria:
- each mode supports a clear user action path,
- outputs remain consistent with core model assumptions.
- Deliverables:
- scheduled retraining + artifact pinning,
- drift detection command,
- feedback-aware retraining path,
- MLflow security remediation and re-audit.
- Acceptance criteria:
- reproducible retraining runs on schedule,
- drift signals are monitored,
- vulnerability audit has no unresolved high/critical items in active stack.