The ID process

• Identifying needs and establishing requirements

• Developing alternative designs that meet those requirements

• Building interactive versions of the designs so that they can be communicated and assessed.

• Evaluating what is being built throughout the process

3 characteristics of this process

• Users should be involved throughout the development of the project

• Specific user experience goals should be identified, agreed upon, and documented

• Iteration through the 4 activities is inevitable

usability goals

efficient to use

effective to use

safe to use

good utility

easy to learn

easy to remember how to use

emotionally fulfilling

fun

rewarding

supportive of creativity

pretty

motivating

helpful

satisfying

entertaining

enjoyable

aesthetic goals

User experience goals

usability goals

efficient to use

effective to use

safe to use

good utility

easy to learn

easy to remember how to use

emotionally fulfilling

fun

rewarding

supportive of creativity

pretty

motivating

helpful

satisfying

entertaining

enjoyable

aesthetic goals

Key goals for an Internet application that allows the general public to access their medical records?

usability goals

efficient to use

effective to use

safe to use

good utility

easy to learn

easy to remember how to use

emotionally fulfilling

fun

rewarding

supportive of creativity

pretty

motivating

helpful

satisfying

entertaining

enjoyable

aesthetic goals

Key goals for a system for teaching college level courses on-line, including lectures?

Understanding and conceptualizing interaction

Conceptualizing web usage

• How do people conceptualize web pages in their everyday activity?

– To what is it similar? What metaphors do they bring to bear?

– What actions can on perform on or with a web page?

Conceptual model

• Need to first think about how your audience will conceptualize the system (e.g. how they will understand it).

First steps in formulating a conceptual model

• What will the users be doing when carrying out their tasks?

• How will they think about the task?• What concepts and metaphors will

they bring with them to the system?

• What interaction modes will be most useful?

Conceptual models

• Many ways of classifying them• We’ll look at activities and objects• And interface metaphors

Conceptual models based on activities

Conceptual models based on activities

• Giving instructions– issuing commands using keyboard and function

keys and selecting options via menus

• Conversing– interacting with the system as if having a

conversation (e.g., AskJeeves)

• Manipulating– acting on objects and interacting with virtual

objects (e.g., pong, MS Word)

• Browsing– Looking through lists, poking around, etc.

1. Giving instructions

• Where users instruct the system and tell it what to do– e.g. print a file, save a file

• Very common conceptual model, underlying a diversity of devices and systems– e.g. DVD player, vending machines

• Main benefit is that instructing supports quick and efficient interaction

• What instructions are needed to get a can of soda?• What instructions are necessary for retrieving a

snack?

2. Conversing• Underlying model of having a conversation

with another human

• Range from simple voice recognition menu-driven systems to more complex ‘natural language’ dialogues

• Examples include timetables, search engines, advice-giving systems, help systems

• Recently, much interest in having virtual agents at the interface.

• AT&T developed voice interaction systems now in use on almost every customer support line.

Get me off the list

1-888-567-8688

3. Manipulating and navigating

• Involves dragging, selecting, opening, closing, etc. on virtual objects

• Exploit’s users’ knowledge of how they interact in the physical world

• Exemplified by:– The direct manipulation approach (DM)– What you see is what you get (WYSIWYG)

Principles of direct manipulation

• Continuous representation of objects and actions of interest

• Physical actions and button pressing instead of issuing commands

• Rapid reversible actions with immediate feedback on object of interest

What are the advantages?

• For novice users?• For experienced users?• For intermittent users?

Why are direct manipulation interfaces so enjoyable?

• Novices can learn the basic functionality quickly• Experienced users can work extremely rapidly to carry

out a wide range of tasks, even defining new functions • Intermittent users can retain operational concepts over

time• Transparency• Users can immediately see if their actions are furthering

their goals and if not do something else• Error messages rarely needed• Users experience less anxiety• The system itself teaches one how to use it.

Disadvantages?

What are the disadvantages with DM?

• Some people take the metaphor of direct manipulation too literally

• Not all tasks can be described by objects and not all actions can be done directly

• Some tasks are better achieved through delegating– e.g. spell checking

• Can become screen space ‘gobblers’• Moving a mouse around the screen can be slower

than pressing function keys to do same actions

4. Exploring and browsing

• Similar to how people browse information with existing media (e.g. newspapers, magazines, libraries, pamphlets)

• Information is structured to allow flexibility in way user is able to search for information– e.g. multimedia, web

Conceptual models based on objects

Conceptual models based on objects

• Usually based on an analogy with something in the physical world

• Examples include books, tools, vehicles

• Classic: Star Interfacebased on officeobjects

Johnson et al (1989)

Movie maker exercise

Movie maker

• Define a conceptual model for a movie making piece of software

Movie maker

• First, what are the objects?

Movie maker

• Objects– Frames– Effects– Transitions– Others?

Movie maker

• Now define a model for how people will construct a movie using the objects.

Which conceptual model is best?

• Direct manipulation is good for ‘doing’ types of tasks, e.g. designing, drawing, flying, driving, sizing windows

• Issuing instructions is good for repetitive tasks, e.g. spell-checking, file management

• Having a conversation is good for specialized applications (e.g., applications for learning, computer-phobic, disabled users and CRM)

• Hybrid conceptual models are often employed, where different ways of carrying out the same actions is supported at the interface - but can take longer to learn