Master’s thesis · FH JOANNEUM
Should AR glasses wait to be asked?
You pick up a product in a shop. The assistant on your glasses already has its facts. Should it wait, offer, or just show them?
Question
The answer is usually on the package. Getting it out is the problem: small print, foreign labels, and facts that say what’s inside but not what it means for you. The usual fix today is the phone. A head-worn display could show the facts while the product stays in your hand, and then the design question is when to show them.
Display glasses are now sold to consumers, so when such an assistant should speak is becoming a product decision. The frame is Horvitz’s mixed-initiative work: a system can wait, ask, or act. The study runs on a Meta Quest 3, standing in for those glasses.
Ask, Offer, or Show? An Exploratory Comparison of Initiation Policies for Product Information on a Head-Worn AR Display.
- RQ1
How do the three policies differ in perceived interruption and in welcomeness?
- RQ2
How do they differ in perceived control over the decision, correctness, decision time and workload?
- RQ3
When do people accept, dismiss, ignore or request the help, and why?
Three policies
You startThe assistant starts
- A
On-demand
Nothing appears until you ask with a pinch.
- B
Offer-first
A small, silent prompt offers information. Pinch to open it, or ignore it and it goes away.
- C
Automatic
The information appears by itself.
The information, its layout and the gestures are the same in all three. What differs is how the help starts: who picks the moment, and whether a prompt comes first. Earlier studies compared these levels with robot assistants and in written scenarios. Their results point in different directions on whether offering first helps.
What it adds
Evidence
Estimates, with confidence intervals, of how much interruption and how much well-timed help each policy produces while people choose among physical products in a lab.
The instrument
The Quest 3 prototype and the specification of each policy, published in full after data collection.
Design implications
On when and how an assistant should start helping, drawn from interviews and behaviour logs.
Peng et al. and Kraus et al. tested robot assistants on laptop tasks, and Harari and Amir used written scenarios about work; in Peng’s study and Harari and Amir’s scenarios, the help itself also changed between conditions. On headsets, Sensible Agent offers help and generates its answer after confirmation, but has no automatic version and changes input modality between conditions. Wang et al. compare proactive and reactive help on a Vision Pro, with no offer step.
The open comparison: on-demand, offer-first and automatic delivery of identical content, on one head-worn display, while a person decides about a product in their hand.
Survey
Most of the 20 want help, and a way to turn it off.
20 shoppers. A small, formative sample that shaped the design. Who should start the help came from the literature, not the survey.
“If it suggests anything without my asking. Like all the ads we face on screens.”
Survey respondent, on unasked suggestions
Study
Setup
- Design
- Within-subjects, Williams-balanced. Everyone uses all three policies. Each round opens with a short script saying how information will appear, and order is modelled in the analysis.
- Participants
- 24 adults aged 18–29. Groups of six are added, up to 36, only if the 95% confidence intervals are still too wide.
- Tasks
- 9 product decisions, each against a stated goal, at a lab shelf of mock products.
- Device
- Meta Quest 3, video passthrough.
Measures
- Primary
- Perceived interruption, rated in neutral wording. Welcomeness: whether information appeared when the participant wanted it, three items per round. Both use items written for this study and checked in the pilots.
- Secondary
- Perceived control, decision correctness, decision time, NASA-TLX, SUS
- Behaviour
- Offers, accepts, dismissals, timeouts and requests, logged
- Qualitative
- Retrospective interview, coded with a second coder
Status
Supervised by Michael Kernbichler.
My part: I ran the survey, designed the study, and designed and built the Quest 3 prototype.
- Survey
20 shoppers on what help they want
- Study design
Policies, tasks, products and measures chosen
- Prototype
Quest 3 build: held-product tracking, three policies, pinch gestures, logging
- Pilots
Technical, then procedural. Questionnaire scoring fixed, then the protocol frozen and pre-registered
- Main study
Data collection, following the frozen protocol
- Analysis & writing
Paired contrasts with confidence intervals, interview themes
Writing
Notes from the research.
Teaching a Headset What Is in Your HandBuilding the study prototype on a Quest 3. What failed, the turn from recognising objects to finding shapes, why the products became cardboard, and what is left before the pilots.
Ask, Offer, or Show: The Study as It StandsThe question the thesis ended up with, the studies it builds on, and how the comparison is set up so that a difference can be traced to one design decision.
Twenty People, a Pile of Papers, and Three Things I Got WrongHow a survey, a lot of reading and three corrections narrowed a whole shopping assistant down to one question: who should start the help.