1. Material from Authors of Human Computer Interaction Alan Dix, et al
User Support
Material from
Authors of Human Computer Interaction
Alan Dix, et al

2. Overview Users require different types of support at different times.
Basic requirements
available but unobtrusive
accurate and robust
consistent and flexible
Design of user support must take account of:
presentation issues
implementation issues

3. Types of Support Quick reference Task specific help Full explanation
Tutorial

4. Types of support Quick reference Task specific help
reminder of details; assumes familiarity
eg command syntax, options, etc.
Usage: telnet [-8] [-#] [L] [-a] [-d] [-e char]
[-l user] [-n tracefile] [-r] [host-name [port]]
Task specific help
addresses problems with particular tasks
focused on what is currently being done

5. Types of Support Full explanation Tutorial
for more experienced and inquisitive users
likely to include information not needed now
Unix man command
Tutorial
aimed at new users

6. Types of support Four types are complementary
Together they support range of points in user’s experience with system
Each type may be on-line and off-line (documentation)
should be consistent in content
presentation medium may have impact on design
general principles for both

7. Requirements Availability Accuracy and Completeness Consistency
Robustness
Flexibility
Unobtrusiveness

8. Requirements Availability Accuracy and completeness Consistency
accessible any time during application interaction
Accuracy and completeness
consider incremental update/feature-adding of releases
Consistency
different parts of help system and documentation consistent in content, terminology and presentation

9. Requirements Robustness Flexibility Unobtrusiveness
system itself should be robust
even more important with support, because users are in trouble when using it
Flexibility
meets needs of user allows user to get information in an appropriate form
context sensitive or adaptive help systems
Unobtrusiveness
shouldn’t block work in application

10. Approaches to User Support
Command Assistance
Command Prompts
Context-Sensitive help
On-line tutorials
On-line documentation
Wizards
Assistants

11. Approaches to user support
Command assistance
good for reference on command, eg man or help
user must know what to look for
Command prompts
provide information when error occurs
good for syntactic errors
won’t tell you if you need a different command
Context sensitive help
depends on what user is doing
eg. completing a dialog, tool tip

12. Approaches to User Support
On-line tutorials
introduces user to components of system
structure progress, maybe at user’s own speed
includes examples, test environment to simulate interface
useful, but inflexible
On-line documentation
printed material in electronic form
eg readme files
continually available but can be difficult to browse
Hypertext can support browsing

13. Approaches to User Support
Wizards
task specific tool that leads user through task step-by-step
user answers ‘questions’ along the way
constraining - may not offer options
should have progress indicator and allow back up

14. Approaches to User Support
Assistants
monitor user behavior and offer suggestions
unobtrusive and under user control
‘Clippy’ not unobtrusive, suggestions inappropriate
MS XP smart tags appear near object of interest

16. Intelligent Help: Adaptive Help Systems
Use knowledge of the user, task, domain and instruction to provide help adapted to user’s needs.
Problems:
Knowledge requirements considerable
must collect data on by monitoring interaction
Issue of control - how active?
What should be adapted?
What is scope of adaptation? :

17. Knowledge representation: User modeling
single, generic user (non-intelligent)
user-configured model (adaptable)
system-configured model (adaptive)
Static help systems can’t address all user differences.
Adaptive help systems model users, refining the model by monitoring a user’s activities, and present help tailored to the particular user.

18. Approaches to User modeling
Quantification
user moves between levels of expertise based on quantitative measure of what he knows
Move from level 1 to level 2 if
system has been used more than twice
commands x and y used effectively
help has not been accessed in this session
system has been used in last 5 days

19. Approaches to User modeling
Stereotypes
user is classified into a particular category
Overlay
an idealized model of expert use is constructed
actual use compared to it
can determine how far user is from optimal use
can suggest optimal use strategies

20. Knowledge representation: Domain and Task Modeling
Usually involves analysis of command sequences
Assistants and agents
Covers
common errors and tasks
command sequences for current task
Problems
interleaved tasks
user intention

21. Techniques for Knowledge representation
Rule-based
Frame-based
Network-based
Example-based

22. Techniques for Knowledge Representation
Rule-based
knowledge represented as rules
facts interpreted using inference (logic)
used in large domains
IF command is EDIT file 1
AND last command is COMPILE file 1
THEN task is DEBUG
action is describe automatic debugger

23. Techniques for Knowledge Representation
Frame-based
knowledge stored in structure that contains labeled slots
slot has default value
useful in small domains
User
Expertise level: novice
Command: EDIT file 1
Last command: COMPILE file 1
Errors this session: 6
Action: describe automatic debugger

24. Techniques for Knowledge Representation
Network-based
knowledge represented as relationships between facts
can link frame-based representations
CC is and instance of COMPILE
COMPILE is a command
COMPILE is related to DEBUG
COMPILE is related to EDIT
Automatic debugger facilitates DEBUG

25. Techniques for Knowledge Representation
Example-based
knowledge represented within decision structure of classification system
trained to classify rather than programmed with rules (AI techniques
detects recurrent features
EDIT file 1
COMPILE file 1
trains for task debug

26. Problems with knowledge representation and modeling
Knowledge difficult to elicit
especially if domain expert not available
variability of users
difficult to ensure completeness and correctness
Interpretation of information
during interaction all we have are logs
do not have user’s intent or goal

27. Other issues Initiative Effect Scope
Does user retain control or can system direct the interaction?
Can system interrupt user to offer help?
Effect
Model only what is needed to satisfy requirements of help system
Scope
Is modeling at application level only or at system level?

28. Designing User Support
User support is not an ‘add on’ - it should be designed integrally with system.
Should concentrate on content and context of help rather than technological issues
There are presentation issues and implementation issues

29. Designing User Support : Presentation issues
How is help requested?
Command
button
function (on/off)
separate application
How is help displayed?
New window
whole screen or split screen
pop-up box
hint icons

30. Designing User Support : Presentation issues
Effective presentation requires
clear, familiar, consistent language
instructional rather than descriptive language
avoid of blocks of text
summary and example

31. Designing User Support Systems : Implementation Issues
Is help
OS command
meta command
application
What resources are available
screen space
memory capacity
speed

32. Designing User Support Systems: Implementation Issues
Structure of help data
single file
file hierarchy
database
Consider
flexibility and extensibility
hard copy
browsing

33. Summary Users require different support at different times
User support should be:
available but unobtrusive
accurate and robust
consistent and flexible
User support comes in a number of styles:
command-based, context sensitive help
tutorial, online doc, wizards and assistants
adaptive help
Design of user support must take account of:
presentation and implementation issues