RJ.Raja Jeevan
Product & commerce
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Metric catalogue for vision checkout and unattended retail: reference design

Deliverable | Retail technology | KPI framework | Reference design, no targets or results

How to use this catalogue

The author contributed domain expertise to solutions of this kind at a medium-scale, product-based company based out of Dallas and Coimbatore. This catalogue is a reference design. It lists measures that a retailer or vendor can choose from when running a vision-based checkout or an unattended store. It sets no targets and reports no results, because targets depend on a store’s own baseline.

Pick a small set for a pilot: one or two from each family below, plus the gates the programme agrees in advance. The recognition and exception families explain whether the system works. The dispute and loss families explain whether it is safe to scale. The data operations family explains whether it will keep improving. Each measure should be reported against a baseline, split by site and item class, and reviewed weekly during a pilot.

Every measure includes a definition, a unit, a suggested review frequency and a typical owner. Frequencies and owners are suggestions.

Recognition accuracy

IDMeasureDefinitionUnitReviewOwner
K01Item-level precisionShare of recognised items that are correct%DailyModel owner
K02Item-level recallShare of items on the tray that were recognised%DailyModel owner
K03Basket-exact rateShare of baskets where every item and quantity is correct%DailyModel owner
K04Top-1 class accuracyShare of items where the top prediction is correct%Per releaseModel owner
K05Top-3 class accuracyShare of items where the right class is in the top three%Per releaseModel owner
K06Fine-grained confusion rateShare of errors between look-alike items (sizes, flavours, variants)%WeeklyModel owner
K07Occlusion error rateError rate on baskets with touching or stacked items%WeeklyModel owner
K08Unrecognised-item rateShare of items the model declines to name%DailyModel owner
K09Unknown-item false match rateShare of out-of-catalogue items named as a catalogue item%WeeklyModel owner
K10Loose and unpackaged item accuracyAccuracy on produce, bakery and other barcode-free goods%WeeklyModel owner
K11Quantity count accuracyShare of multi-unit lines with the correct count%DailyModel owner
K12Calibration errorGap between stated confidence and observed accuracyscorePer releaseModel owner

Basket and checkout quality

IDMeasureDefinitionUnitReviewOwner
K13Basket acceptance rateShare of baskets accepted without human help%DailyStore ops
K14Signal agreement rateShare of baskets where vision, weight and price rules agree%DailyStore ops
K15Weight mismatch rateShare of baskets where weight disagrees with recognition beyond tolerance%DailyStore ops
K16Price rule violation rateShare of baskets that fail a price or promotion rule check%DailyPricing
K17Promotion application accuracyShare of eligible baskets with the correct promotion applied%WeeklyPricing
K18Tray-to-receipt timeMedian time from placing items to receiptsecondsDailyProduct
K19Re-present request rateShare of baskets where the shopper is asked to re-present an item%DailyProduct
K20Abandonment rate at checkoutShare of started checkouts not completed%DailyProduct
K21Payment failure rateShare of accepted baskets whose payment fails%DailyPayments
K22Receipt accuracy complaintsComplaints about receipt content per 1,000 basketscountWeeklyCustomer care
K23Age-restricted item check pass rateShare of restricted items sold with a completed check%DailyCompliance
K24Bag and container handling accuracyAccuracy when items arrive in bags or containers%WeeklyModel owner

Exceptions and assistance

IDMeasureDefinitionUnitReviewOwner
K25Exception rateBaskets sent to a person per 100 basketsrateDailyStore ops
K26Exception rate by causeExceptions split by recognition, weight, price, payment and other%WeeklyStore ops
K27Median time to resolveMedian time from exception raised to resolvedsecondsDailyStore ops
K2895th percentile waitWait for the slowest 5 percent of exceptionssecondsDailyStore ops
K29Attendant touches per 100 basketsStaff interventions per 100 basketsrateDailyStore ops
K30First-contact resolution rateExceptions resolved without escalation%WeeklyStore ops
K31Remote assistance shareShare of exceptions resolved remotely%WeeklyStore ops
K32Exception reopen rateExceptions reopened after resolution%WeeklyStore ops
K33Shopper-initiated help requestsHelp requests per 100 basketsrateWeeklyProduct
K34Staff override rateShare of exceptions where staff override the system suggestion%WeeklyModel owner
K35Exceptions converted to training examplesShare of resolved exceptions stored as labelled data%WeeklyData ops
K36Exception queue backlogOpen exceptions at peakcountDailyStore ops

Disputes and customer trust

IDMeasureDefinitionUnitReviewOwner
K37Dispute rateDisputed baskets per 1,000 basketsrateWeeklyCustomer care
K38Dispute upheld rateShare of disputes resolved in the shopper’s favour%WeeklyCustomer care
K39Time to dispute resolutionMedian time from dispute to refund or closurehoursWeeklyCustomer care
K40Wrongful-charge rateBaskets charged for items not taken per 1,000rateMonthlyCustomer care
K41Missed-charge rateBaskets that omitted items taken per 1,000 (from audits)rateMonthlyLoss prevention
K42Repeat-use rateShare of shoppers who use the lane or store again within 30 days%MonthlyProduct
K43Satisfaction scorePost-checkout satisfaction ratingscoreWeeklyProduct
K44Trust complaintsComplaints about accusations or monitoring per 1,000 basketscountMonthlyCustomer care

Loss and shrink

IDMeasureDefinitionUnitReviewOwner
K45Total shrink rateInventory loss as a share of sales%MonthlyLoss prevention
K46Lane-attributed unknown lossUnknown loss attributed to the lane or format% of salesMonthlyLoss prevention
K47Non-scan or non-recognition rateItems taken but not registered (audit-based)%MonthlyLoss prevention
K48Item substitution rateCheaper item presented for a dearer one (audit-based)rateMonthlyLoss prevention
K49Audit mismatch rateMismatch found in sampled basket audits%MonthlyLoss prevention
K50Malicious loss shareShare of lane losses judged intentional%QuarterlyLoss prevention
K51Accidental loss shareShare of lane losses from honest error%QuarterlyLoss prevention
K52High-risk item loss rateLoss rate on the top 50 items by theft risk%MonthlyLoss prevention
K53Door or exit breach eventsExits without a completed basket in controlled formatscountWeeklyStore ops
K54Wastage rateSpoiled or damaged stock as a share of sales%MonthlyStore ops
K55Refund abuse indicatorsRefund requests flagged by pattern rulescountMonthlyLoss prevention
K56Loss by shift or hour bandLoss split by time of day% of salesMonthlyLoss prevention

Inventory and restocking

IDMeasureDefinitionUnitReviewOwner
K57On-shelf availabilityShare of catalogue items in stock at a sampled time%DailyStore ops
K58Out-of-stock durationMedian time an item stays out of stockhoursWeeklyStore ops
K59Inventory record accuracyShare of items whose system count matches a physical count%MonthlyStore ops
K60Planogram complianceShare of shelf positions holding the planned item%WeeklyStore ops
K61Restock task completion timeMedian time from restock task raised to doneminutesWeeklyStore ops
K62Restock error rateRestock actions that changed shelf layout without update%WeeklyStore ops
K63Days of coverAverage days of stock on handdaysWeeklySupply chain
K64Stock variance after auditSystem count minus counted stock, absoluteunitsMonthlyStore ops

Operations and availability

IDMeasureDefinitionUnitReviewOwner
K65System uptimeShare of opening hours the format is fully operating%DailyEngineering
K66Edge-offline operation shareTime operating on local fail-safe due to network loss%WeeklyEngineering
K67Camera or sensor fault rateFaults per device per monthrateMonthlyEngineering
K68Mean time to repairMedian time from fault to restorationhoursMonthlyEngineering
K69Door unlock latencyMedian time from authentication to door opensecondsWeeklyEngineering
K70Basket decision latencyMedian time to assemble and score a basketsecondsWeeklyEngineering
K71Software release failure rateReleases that need rollback%MonthlyEngineering
K72Support ticket volumeSupport tickets per site per weekcountWeeklySupport

Commercial and labour

IDMeasureDefinitionUnitReviewOwner
K73Sales per site per dayDaily sales by sitecurrencyDailyFinance
K74Transactions per hourBaskets per open hourcountDailyFinance
K75Average basket valueSales divided by basketscurrencyWeeklyFinance
K76Staffed hours per 1,000 basketsLabour hours needed per 1,000 basketshoursMonthlyFinance
K77Labour hours redeployedHours moved to other taskshoursMonthlyStore ops
K78Cost per basketAll-in operating cost per basketcurrencyMonthlyFinance
K79Pilot-versus-baseline sales changeSales change against the site’s own baseline%MonthlyFinance
K80Payback periodTime for net savings to cover investmentmonthsQuarterlyFinance

Model and data operations

IDMeasureDefinitionUnitReviewOwner
K81Time to add a new itemTime from item first seen to live recognitiondaysWeeklyData ops
K82Catalogue coverageShare of sold items the model can recognise%WeeklyData ops
K83Images per itemMedian labelled real images per catalogue itemcountMonthlyData ops
K84Label-error rateShare of audited labels found wrong%Per releaseData ops
K85Reviewer acceptance rateShare of model proposals accepted unchanged%WeeklyData ops
K86Review time per imageMedian time to review one imagesecondsWeeklyData ops
K87Holdout accuracy trendAccuracy on the frozen real holdout across versions%Per releaseModel owner
K88Synthetic-to-real gapAccuracy on synthetic validation minus real holdoutpointsPer releaseModel owner
K89Drift alert countAlerts for input or prediction driftcountWeeklyModel owner
K90Retraining cycle timeTime from data cut to production modeldaysPer releaseModel owner
K91Packaging-change detection timeTime to detect a packaging change after it reaches shelvesdaysMonthlyData ops
K92Inter-reviewer agreementAgreement between reviewers on a shared sample%MonthlyData ops

Privacy and governance

IDMeasureDefinitionUnitReviewOwner
K93Image retention complianceShare of images deleted within the retention limit%MonthlyPrivacy
K94Access audit findingsUnauthorised or unexplained access eventscountMonthlyPrivacy
K95Signage complianceSites with required monitoring notices in place%QuarterlyPrivacy
K96Data subject requests closed on timeRequests answered within the required period%MonthlyPrivacy
K97Pilot gate statusGates passed, at risk or failedstatusWeeklyProgramme
K98Rollback readinessSites able to revert to conventional checkout within an agreed time%QuarterlyProgramme

Suggested pilot starter set

A pilot scorecard of about twelve measures is easier to run than the full list. A reasonable starter set draws from each family:

  • Recognition: K03 basket-exact rate, K08 unrecognised-item rate.
  • Basket quality: K13 basket acceptance rate, K18 tray-to-receipt time.
  • Exceptions: K25 exception rate, K27 median time to resolve.
  • Disputes: K37 dispute rate, K40 wrongful-charge rate.
  • Loss: K45 total shrink rate, K49 audit mismatch rate.
  • Data operations: K81 time to add a new item, K87 holdout accuracy trend.

Notes and method

This catalogue is a synthesis by the author from domain knowledge, informed by public research on self-checkout loss and retail checkout recognition: ECR Retail Loss, Global Study on Self checkout loss in Retail (https://ecrloss.com/research-paper/self-checkout-retail-loss-global-study/), the National Retail Federation National Retail Security Survey 2023 (https://nrf.com/research/national-retail-security-survey-2023) and the RPC retail product checkout dataset (https://arxiv.org/abs/1901.07249). The catalogue is a reference design. It contains no measured results, and no vendor claims were used.

Teams that want help turning this into a pilot scorecard can book a working session with the author through Topmate: https://topmate.io/raja_jeevan_kumar_maduri