user support
DESCRIPTION
User Support. Material from Authors of Human Computer Interaction Alan Dix, et al. 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: - PowerPoint PPT PresentationTRANSCRIPT
User Support
Material from
Authors of Human Computer Interaction
Alan Dix, et al
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
Types of Support
Quick reference Task specific help Full explanation Tutorial
Types of support
Quick reference 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
Types of Support
Full explanation for more experienced and inquisitive users likely to include information not needed now Unix man command
Tutorial aimed at new users
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
Requirements
Availability Accuracy and Completeness Consistency Robustness Flexibility Unobtrusiveness
Requirements
Availability 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
Requirements
Robustness 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
Approaches to User Support
Command Assistance Command Prompts Context-Sensitive help On-line tutorials On-line documentation Wizards Assistants
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
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
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
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
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? :
Knowledge representation: User modeling 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.
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
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
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
Techniques for Knowledge representation
Rule-based Frame-based Network-based Example-based
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 1THEN task is DEBUG action is describe automatic debugger
Techniques for Knowledge Representation Frame-based
knowledge stored in structure that contains labeled slots
slot has default value useful in small domains
UserExpertise level: noviceCommand: EDIT file 1Last command: COMPILE file 1Errors this session: 6Action: describe automatic debugger
Techniques for Knowledge Representation Network-based
knowledge represented as relationships between facts
can link frame-based representations
CC is and instance of COMPILECOMPILE is a commandCOMPILE is related to DEBUGCOMPILE is related to EDITAutomatic debugger facilitates DEBUG
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 1COMPILE file 1
trains for task debug
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
Other issues
Initiative 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?
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
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
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
Designing User Support Systems : Implementation Issues Is help
OS command meta command application
What resources are available screen space memory capacity speed
Designing User Support Systems: Implementation Issues Structure of help data
single file file hierarchy database
Consider flexibility and extensibility hard copy browsing
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