๐Ÿ›ก๏ธ Data quality, retention & privacy

Set expectations for analytics accuracy, data retention, and privacy protection. This page complements the GDPR and data access article.

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Written by the Merlin Cloud team

Updated 20 August 2025


Data quality: what affects accuracy

Session based model

  • Counts are session based, not unique people.

  • Kiosks dedupe by session ID on upload.

  • Cameras do not track identities and do not backfill offline gaps.

Known edge cases

  • Mirrors and reflective surfaces can inflate counts.

  • Heavy crowding or occlusion reduces detection accuracy.

  • Extreme lighting or motion blur can lower detection confidence.

  • Poor camera placement or narrow field of view leads to missed movement.

Clock drift and timing

  • Device clock drift is reduced using server receipt time, IP based location, and heartbeat monitoring.

  • Analytics use UTC so comparisons are stable across daylight changes.

Offline behaviour

  • Kiosks: events queue in localStorage and upload later; numbers update on next refresh.

  • Cameras: no buffering when offline; gaps appear as lower totals.

Quality signals in the UI

  • The dashboard does not surface sampling warnings or thresholds. If numbers look unusual, check device online status, placement, lighting, and your filters.

Practical ways to improve quality

  • Mount cameras high and angle slightly downward to reduce occlusion.

  • Avoid mirrors and direct backlighting in the scene.

  • Validate with a quick walk test after drawing zones or lines.

  • Keep zones simple: prefer 4 or fewer per camera for clarity.

  • Use the same time window when comparing periods.

Retention and deletion

Analytics events and configuration

  • Sessions, experiences, and campaigns use soft delete archiving by default.

  • No fixed retention on raw analytics events unless agreed; enterprise retention can be configured.

Camera frames

  • If frame storage is enabled for security or validation, frames are deleted after 6 months.

Heatmaps

  • We store computed overlays, coordinates, and density values, not full video.

Exports

  • CSV files you download are under your control. Store and delete them according to your policy.

Right to erasure

  • Submit requests through support. We will act on applicable records and logs as your Processor.

Privacy posture

  • No facial recognition and no identity tracking.

  • Cameras are processed server side and anonymised immediately after detection runs.

  • Kiosk analytics redact sensitive inputs. Local caches can be encrypted at rest for enterprise.

  • Access is role based: Admin global, Manager and Viewer scoped to assigned countries.

  • Transport security: HTTPS with TLS 1.2 or 1.3.

Roles and access

  • Admin: view all analytics, audit logs, and configuration.

  • Manager: read and write within assigned countries.

  • Viewer: read only within assigned countries.

Checklist for compliance and quality

  • Post an in-store notice about analytics in use.

  • Run a DPIA if required by your regulator or policy.

  • Review placement and lighting for each camera.

  • Keep kiosk media optimised and devices online daily.

  • Set internal retention rules for exports and reports.


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