Usability Standards for Biometric Systems: Options, Opportunities, Resources

1. Usability Standards for Biometric Systems: Options, Opportunities, Resources Marek Rejman-Greene Home Office Scientific Development Branch, UK International Workshop on Usability & Biometrics

2. Why support the user in a biometric system? • Effectiveness • for operator/end user • Efficiency • for operator/end user • Accessibility • for (partially, multiply) disabled • Cultural accessibility • reduce dependency on written instructions • Reduction of ‘User discomfort’ • in unfamiliar/stressful/encumbered situations International Workshop on Usability & Biometrics

3. Aims of talk • Introduce current standardisation activities • Pictograms, Icons and Symbols • Discuss required research • Identify wider context of biometric usability standards • In the context of the end-to-end user experience • IRIS entry into UK • US-VISIT exit trial in Baltimore • Portuguese RAPID entry-exit (Faro, Lisbon, Oporto) International Workshop on Usability & Biometrics

4. Current standardisation efforts • ISO/IEC WD 24779: • Pictograms, Icons and Symbols for Use with Biometric Systems • WD 37N2244 • NIST Comments: 37N2603 International Workshop on Usability & Biometrics

5. ISO/IEC WD 24779 • Recognition Scenarios: • Verification, Identification: Yes • Enrolment: No • in general, this is supervised • Required symbols: • General use of biometric device and its type/modality • eg. Facial recognition or fingerprints • Where to stand, look or to place finger. • Wait (or hold steady): for process to complete • Success: process complete • Failure • Re-try (the same characteristic) • Try another finger or eye • CDN: Seek human assistance • Give up • ISO standardisation for ICONS International Workshop on Usability & Biometrics

6. Other components • Presentation of identifier or document or token • entry of numeric identifier • placement of document • placement of token • no identifier or document required • Other information: • privacy/data protection assurance, redress mechanisms, responsible authority • Other actions: • request human intervention • restart • contextual help International Workshop on Usability & Biometrics

7. ISO Icon design process • identification of need for the graphical symbol • description of the purpose • of the graphical symbol and identification of any orientation considerations • unique title • analysis of • characteristics of the intended users, • the task involved • context of use • existing or proposed symbol originals • in the same and/or related fields; • design of a symbol • legibility and comprehension of the graphical symbol International Workshop on Usability & Biometrics

8. Symbol families • Information • Directional • Feedback International Workshop on Usability & Biometrics

9. NIST testing: Phase 1 • Participant group: 13 NIST employees • Background: different educational backgrounds and disciplines • English as 2nd language: 3/13 • Nationality: n/s • Age: mid-20’s to early 60’s • Gender: n/s • Pre-condition: all NIST employees have been fingerprinted • Setting: Interview in office of participants • Context • 9/13: description as approach to immigration • last 4/13: mock fingerprint scanner placed on desk • Data collection: • interview about symbol meaning before and after description of process International Workshop on Usability & Biometrics

10. NIST testing: Phase 2 • Participant group: 44 volunteers from Washington DC • Background: Range of educational and professional • English as 2nd language: all • Nationality: Wide international origin • Age: 25 –70 • Gender: ~ 50:50 • Precondition: no work experience in biometrics • Setting: briefing room, followed by testing room • Context: Instructions to follow symbols and leave 10 fingerprints on mock scanner • Data collection: Talk-aloud protocol International Workshop on Usability & Biometrics

11. NIST testing: Results • Phase 1: Number of alternative symbols rejected • Phase 2: • Results: • almost everyone ok: with order and sequence • generally ok: redo, time, get help • Problems: • when additional symbols used, eg pressure in addition to placement • unsure when to remove hand from scanner International Workshop on Usability & Biometrics

12. Other support during process • During finger placement: • Wait/hold • Press more/less • Move finger(s) to left/right • Move finger(s) up/down • Rotate finger(s) till align • Indication of which finger(s) to perform action on • Removal of finger/hand from scanner Bold: already considered Italics: not yet considered International Workshop on Usability & Biometrics

13. Other dimensions • Illumination • Animation • Sound • Tactile International Workshop on Usability & Biometrics

14. Wider context of the system - questions • Baecker, Small and Mander (1991) • Context of animation • Identification: what is this? • Transition: where have I come from or am going to? • Orientation: where am I? • Choice: what do I do now? • Demonstration: what can I do with this? • Explanation: how can I do this? • Feedback: what is happening? • History: what have I done? • Interpretation: why did that happen? • Guidance: what should I do now? International Workshop on Usability & Biometrics

15. Usability of biometrics in system context - 1 • Recognition of the existence of the biometric option • ahead of time • Chunking of information • check entitlement; present document; position self correctly • Classes of subjects allowed to exercise option • entitled parents with children may not be entitled any longer • Cost-benefit to user • costs/benefits of being seen to step out of line • cost reduction if follow others (sheep effect) • cost increase if fails to work for user (rejection, embarrassment) International Workshop on Usability & Biometrics

16. Usability of biometrics in system context - 2 • Attractors/Distractors • positioning (too high, too low) • Information • at the right time (continuously running videoclip) • How do I get started? • Encumbrances • baggage, tickets • What do I do next? • How do I summon help? • Too much help!! • users abrogate responsibility – leave passport in reader • When is it finished? • US-VISIT: finger, face, ticket International Workshop on Usability & Biometrics

17. Usability of biometrics in system context - 3 • Are the subjects’ mental models the same as operators’? • users not clear about face recognition as the purpose • logical order of presentation of fingerprints • Following other subjects’ actions • delay effect • Expectations of timing • feedback in IRIS • chip reading time for UK passport International Workshop on Usability & Biometrics

18. Testing and reporting of results • Early work by NPL within EU’s project, BIOTEST • Within the framework of ISO/IEC WD 19795? • technology, scenario, operational • in particular, Biometric Performance Testing And Reporting -- Part 6: Testing Methodologies for Operational Evaluation? • End-to-end system performance, segmented processes • Issues: • Subject demographics • especially (non) habituated, (un)motivated, stressed, encumbered, disabled • Inclusion of other users, • e.g. those no longer entitled, as they are accompanied by children • inclusion of attempts by those not entitled • levels of awareness International Workshop on Usability & Biometrics

19. Summary • Work on icon standard started • definition of complete set of icons? • Research required • NIST studies as a pathfinder • relationship to existing icons in the environment of use • accessibility of icons • Usability of the wider system • how does this fit in with 24779? • Testing and reporting • within current biometric testing framework? International Workshop on Usability & Biometrics