InfoCamp 2009
User Interface
Responsiveness
Instantaneous
Immediate
Continuous
Captive
Steve Seow | User Researcher | Microsoft Surface
Rajesh Kalidindi | User Researcher | Microsoft IT
About Steve…
 Academic: Experimental
Psychology
 Human Timing, Time Perception,
Human-Computer Interaction
 Professional: User Researcher
 Microsoft Surface
 Spare time: Author
 Designing and Engineering Time
About Rajesh…
 Academic:
 Economics, PG in Computer Applications
 Certified Usability Analyst
 Professional: User Researcher
 Microsoft IT
 Spare time:
 Observe
Overview…
Barnabus Effect
Defining Responsiveness
Classes of Responsiveness
The Barnabus Effect…
Clip 1
The Barnabus Effect…
Clip 2
The Barnabus Effect…
1. WYSMNBWYG:
- What you see may not be what you get!
2. Your brain plays tricks on you all the time!
… so don’t trust your brain!
Scholarly note: Look up Attenuation Hypothesis
defining...
relsponlsivelness
relsponlsivelness
the ability of a system to respond to
user input and process internal
operations without undue delay.
Responsiveness is…
1. relative to the interaction in question
• Reflex < Reaction < Verbal Acknowledgment
• Key press < Local search < Large Data download
2. subjectively perceived & interpreted
• A two-hour documentary = boring or captivating?
• Two-hour virus scan = good or bad?
3. non-exclusive in its form
• Street signs : Landmarks, structures, etc.
• Notification: HDD thrashing, LED blinking, etc.
Industry Standards
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
1472 = MLT-STD-1472F
C = Card et al (1990)
ESD = ESD/MITRE
M = Miller (1968)
Metric A
Interaction A
Metric B
Interaction B
Metric C
Interaction C
?
Interaction C
Version 2.0
Metric
Interaction
Interaction
Metric User Expectancy
Interaction
Interaction
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
0.1 sec
Key Response (1472) Perceptual Processing (C)
Instantaneous system response (M)
Response to menu selection by key (ESD)
0.2 sec
Key Print (1472)
Max for displayed feedback in normal data entry (ESD)
Pointing (from input to display) and Sketching (1472)
0.5 sec
Min for simple data request, next page (ESD)
Page Scan (1472)
Local database update (1472)
1 sec
Page Turn (1472) Immediate Response (C)
Max for simple data request, next page (ESD)
Max for no feedback (M)
2 sec
Max for simple data entry (ESD)
Min for error messages (278) Error feedback (1472)
Response to selection of command (1472)
Non-local database update (1472)
4 sec
Max for error messages (ESD)
10 sec
Max limit for keeping focus on task (M)
Unit Task (C)
Range of maximum
acceptable response time
What users expect
0.1 to 0.2 sec
Instantaneous
0.5 to 1 sec
Immediate
2 to 5 sec
Continuous
7 to 10 sec
Captive
introducing...
classes of
relsponlsivelness
1. Instantaneous (< 0.1 – 0.2 sec)
• Users Expect: Instantaneous behavior
• Analogy: System’s Nerves, Senses, etc.
• R.o.T: Anything that mimics physical objects
• Examples: Key-press, GUI button press, etc.
RoT: Rule of Thumb
2. Immediate (< .5 – 1 sec)
• Users Expect: Acknowledgement
• Analogy: Reflexes, Simple Reaction
• R.o.T: “No-brainer”* operations
• Examples: panning, zooming, viewing “processed” or
ready* data
* = as perceived by users!
3. Continuous (< 2 – 5 sec)
• Users Expect: Uninterrupted Flow
• Analogy: Thinking Time, “Calculated” Reaction
• R.o.T: Periodic progress update, error messages
• Examples: error messages, time-outs, progress
indication
4. Captive (< 7 – 10 sec)
• Users Expect: NOT to be held hostage or
stay idle
• Analogy: System Elevator Pitch
• R.o.T: Attention Span
• Examples: Downloading, Delivery of
consumable information (status, etc.)
Responsiveness Classes
1. Not mathematical model based on a
continuum of “slow to fast”, letter gradeassignment, etc.
• 0 to 1: Superfast.
• 1 to 2: Fast.
• >2 Slow!
2. Psychological, empirical model based on
what users expect.
•
•
So “gaps” are possible (0.1 to 0.2, 0.5 to 1)
Even overlaps could have been possible!
Summary
1. Defining Responsiveness
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

Relative
Subjective
Non-Exclusive
2. Classes of Responsiveness

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
Instantaneous
Immediate
Continuous
Captive
Thank you!
 More Info?
 Steve - SSeow@Microsoft.com
 Rajesh - RaKalidi@Microsoft.com
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

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Blog - http://blogs.msdn.com/time
Book - Designing and Engineering Time
Web - www.Engineering Time.com
Handout: UI Timing Cheatsheet