Lecture 16

user support

Today’s Outline Users have different requirements for

support at different times. User support should be:

available but unobtrusiveaccurate and robustconsistent and flexible.

Today’s Outline User support comes in a number of styles:

command-based methodscontext-sensitive help tutorial helponline documentationwizards and assistantsadaptive help.

Today’s Outline Design of user support must take account

of: presentation issues implementation issues.

Overview Users require different types of support at different

times. There are four main types of assistance that users

require:Quick referenceTask-specific help Full explanationTutorial.

Quick Reference Quick reference is used primarily as a

reminder to the user of the details of tools he is basically familiar with and has used before.

It may, for example, be used to find a particular command option, or to remind the user of the syntax of the command.

Quick Reference -- Telnet

Quick Reference –Word 2007 Screen

Task Specific Help Task-specific help is required when the

user has encountered a problem in performing a particular task or when he is uncertain how to apply the tool to his particular problem.

The help that is offered is directly related to what is being done.

Task Specific Help Example

Task Specific Help --PowerP

Full Explanation The more experienced or inquisitive user

may require a full explanation of a tool or command to enable him to understand it more fully.

This explanation will almost certainly include information that the user does not need at that time.

Full Explanation – Example In Unix, most programs, and many

protocols, functions, and file formats, have accompanying manuals.

With the man command, you can retrieve the information in the manual and display it as text output on your screen.

man --unix

Tutorial This is particularly aimed at new users of

a tool and provides step-by-step instruction (perhaps by working through examples) of how to use the tool.

Tutorial –Mail Merge

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 contentpresentation medium may have impact on

designgeneral principles for both

Requirements of User Support Designing a good help system needs to

understand some features that help system should have.

Using all of these help features is not compulsory for a system.

Requirements Features Availability

continuous access concurrent to main application Accuracy and completeness

help matches and covers actual system behaviour Consistency

between different parts of the help system and paper documentation Robustness

correct error handling and predictable behaviour Flexibility

allows user to interact in a way appropriate to experience and task Unobtrusiveness

does not prevent the user continuing with work

Availability The user needs to be able to access help

at any time during his interaction with thesystem. He should not have to quit the application he

is working on in order to open the help application.

Availability This is a problem for non-windowed

systems if the help system is independent of the application that is running.

However, in windowed systems there is no reason why a help facility should not be available constantly, at the press of a button.

Accuracy and completeness It may seem obvious to state that the

assistance provided should be accurate and complete. if the assistance provided proves not to match

the actual behavior of the system the userwill, at best, become disillusioned with the help facilities, and, at worst, get intodifficulties.

The completeness also is very important.

Consistency Users require different types of help for

different purposes. This implies that a help system may incorporate a

number of parts. The help provided by each of these must be

consistent with all the others and within itself Online help should also be consistent with

paper documentation. It should be consistent in terms of content,

terminology and style of presentation.

Robustness Help systems are often used by people

who are in difficulty, perhaps because thesystem is behaving unexpectedly or has failed altogether.

It is important then that the help system itself should be robust, both by correct error handling and predictable behavior.

Flexibility Many help systems are rigid in that they

will produce the same help message regardless of the expertise of the person seeking help or the context in which they are working.

A flexible help system will allow each user to interact with it in a way appropriateto his needs.

Unobtrusiveness The help system should not prevent the

user from continuing with normal work, nor should it interfere with the user’s application.

Approaches to user support Command assistance

User requests help on particular commande.g., UNIX man, DOS help

Good for quick reference Assumes user know what to look for

This type of help is simple and efficient if the user knows what he wants to know about and is seeking either a reminder or more detailed information.

However, it assumes that the user does know what he is looking for, which is often not the case.

Approaches to user support.. Command prompts

Provide information about correct usage when an error occurs Good for simple syntactic errors Also assumes knowledge of the command

Another form of command prompting, which is not specifically intended to provide help but which supports the user to a limited degree, is the use of menus and selectable icons.

Approaches to user support (ctd)

Context sensitive help help request interpreted according to context in which it occurs.

e.g. tooltips

Approaches to user support On-line tutorials

user works through basics of application in a test environment. can be useful but are often inflexible.

On-line documentation paper documentation is made available on computer. continually available in common medium can be difficult to browse hypertext used to support browsing.

wizards and assistants wizards

task specific tool leads the user through task, step by step, using user’s answers to specific questions

example: resumé useful for safe completion of complex or infrequent tasks constrained task execution so limited flexibility must allow user to go back

Approaches to User Support Assistants

monitor user behavior and offer suggestions

unobtrusive and under user control

‘Clippy’ not unobtrusive, suggestions inappropriate

MS Office smart tags appear near object of interest

Adaptive Help In any large or complex computer system,

users will be familiar with a subset ofthe available functionality, demonstrating expertise in some applications andhaving no experience with others, even to the point of being unaware of theirexistence.

Adaptive Help In addition, different users will have different

needs and levels of understanding. Adaptive help systems attempt to address

these problems. Adapting the help that they provide to the

individual user who is making the request and by actively suggesting alternative courses of action of which the user may not beaware.

Intelligent Help: Adaptive Help Systems

Use knowledge of the context, individual user, task, domain and instruction to provide help adapted to user's needs.

Problems knowledge requirements considerable who has control of the interaction? what should be adapted? what is the scope of the 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

Overlayan idealized model of expert use is

constructed actual use compared to itcan determine how far user is from optimal

usecan suggest optimal use strategies

Knowledge representation: Domain and Task Modeling

Usually involves analysis of command sequences Assistants and agents

Coverscommon errors and taskscommand sequences for current task

Problems interleaved tasksuser intention

Knowledge representation

Advisory strategy

involves choosing the correct style of advice for a given situation.

e.g. reminder, tutorial, etc.

few intelligent help systems model advisory strategy, but choice of strategy is still important.

Techniques for Knowledge representation

Rule-based Frame-based Network-based Example-based

Techniques for Knowledge Representation

Rule-basedknowledge 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-basedknowledge stored in structure that contains

labeled slots slot has default valueuseful in small domains

UserExpertise level: noviceCommand: EDIT file 1Last command: COMPILE file 1Errors this session: 6Action: describe automatic debugger

Techniques for Knowledge Representation

Network-basedknowledge represented as relationships

between factscan 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-basedknowledge 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 availablevariability of usersdifficult to ensure completeness and

correctness

Interpretation of informationduring interaction all we have are logsdo not have user’s intent or goal

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 requiresclear, familiar, consistent language instructional rather than descriptive

languageavoid of blocks of textsummary and example

Designing User Support Systems : Implementation Issues Is help

OS commandmeta commandapplication

What resources are availablescreen spacememory capacityspeed

Designing User Support Systems: Implementation Issues Structure of help data

single file file hierarchydatabase

Consider flexibility and extensibilityhard copybrowsing

Issues in adaptive help Initiative

does the user retain control or can the system direct the interaction? can the system interrupt the user to offer help?

Effect what is going to be adapted and what information is needed to do this? only model what is needed.

Scope is modelling at application or system level? latter more complex

e.g. expertise varies between applications.

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

Summary Design of user support must take account

of: presentation and implementation issues