Interface Guidelines & Principles Focus on Users & Tasks Not Technology

Interface Guidelines & Principles  7 principles for Interface Design 1.Focus on the users & tasks, not technology.  Easier said than done for programmers.

Interface Design vs. Development  Design –Somewhat, creative human activity for interface. –Specifies interface’s appearance & interactions. –Here is where we do mock ups, specs, etc.  Development –Interface production. –Implementation of design. –Here is where Java, C++, HTML, etc. come in  HCC does both

How to focus on users & tasks?  Must asks a few questions in the beginning.

Who  For whom is this product or service being designed?  Who are the customers, users, experts, etc. –Customers = Users = Experts ?  What is the background of the users? –education, culture, ethics, age, sex, etc.

What  What is the product or service for? –What problem does it solve? –What value will it add?  What activity is it intended to support? –What are the skills/knowledge of the users? –What are the motivations for users?

How  How do the users work in the domain now? –How will the product or service fit in or replace it?  How do users conceptualize the tasks now? –How will they conceptualize the tasks later?

User Centered Design

 A way to force yourself to identify and consider the relevant human factors in your design  Helps reduce the number of decisions made out of the blue, and helps focus design activities  Helps document and defend decisions that may be reviewed later

UCD - Know the Users  Ask the Who questions –Skills, background, etc.  Know the user’s job  Possible exception –World Wide Web, who are your users?

UCD – Participatory Design  Participatory Design –The user takes a participatory role in the design process.  Involve the users as much as possible, but don’t over do it. –How many people does it take to screw in a light bulb?

UCD – Design to Prevent Errors  Common errors should be avoided. –rm *.*, delete *.*  Through experience, you will learn how to spot vulnerable areas that are error prone. –Much easier said than done!

UCD – Optimize User Operations  Add shortcuts where necessary.  CAUTION!!! –Shortcuts can be over rated in some systems. –Know your users first and then decide on shortcuts.

UCD – Keep Control with User  The user should be in control or at least think he/she is in control.  Manage user interaction and control point of view.

UCD – Help the User  Provide assistance throughout your system.  The user should be able to get help any time he/she wishes (control point of view).  Help is a difficult task because sometimes users need help with the help.

User Centered Design DESIGN IMPLEMENT USE & EVALUATE

UCD: 9 Step Overview 1.Define the Context 2.Describe the User 3.Task Analysis 4.Function Allocation 5.System Layout / Basic Design 6.Mockups & Prototypes 7.Pilot Test & Usability Testing 8.Iterative Test & Redesign 9.Updates & Maintenance

1. Define the Context  Context: –Life critical systems, applications –Industrial, commercial, military, scientific, consumer –Office, home, entertainment –Exploratory, creative, cooperative  Market  Customer (not the same as the User) …Design Impacts?…

2. Describe the User (!!)  Physical attributes (age, gender, size, reach, visual angles, etc…)  Physical work places (table height, sound levels, lighting, software version…)  Perceptual abilities (hearing, vision, heat sensitivity…)  Cognitive abilities (memory span, reading level, musical training, math…)  Personality and social traits (likes, dislikes, preferences, patience…)  Cultural and international diversity (languages, dialog box flow, symbols…)  Special populations, (dis)abilities

3. Task Analysis  Talk to and observe users (NOT customers) doing what they do  List each and every TASK  Break tasks down into STEPS HABSTRACT into standard tasks (monitor, diagnose, predict, control, inspect, transmit, receive, decide, calculate, store, choose, operate, etc.)

4. Function Allocation  Consider the whole system!  Decide who or what is best suited to perform each task (or each step)  Base this on knowledge of system hardware, software, human users, communications protocols, etc.  Allocation constraints: Effectiveness; Cognitive/affective; Cost; Mandatory

5. System Layout / Basic Design  Summary of the components and their basic design  Cross-check with any Requirements Documents; Human Factors refs; Hardware specs; Budgets  Ensure that the system will support the design and comply with constraints

6. Mockups & Prototypes  “Informed Brainstorming”  RAPIDLY mock up the user interfaces for testing with real people  Pen and paper or whiteboard to start  Iterate, iterate, iterate!!  Increasingly functional & veridical  List audio & visual details at same levels of detail in the prototypes

7. Pilot Test & Usability Testing  Pilot Test –Small usability study before the real study. –Pilot tests are conducted as a prelude to the real usability test. –Helps to refine the usability test process and procedures. –Get preliminary results before the real test.

7. Pilot Test & Usability Testing  Get real (or representative) users to do what they do, using the prototypes  Subjective and objective feedback. Sometimes users “want” features that actually yield poor performance  Video tape, lots of notes  Feedback into the iterative evaluation & redesign of the system  “Discount” usability testing can be very effective, using fewer subjects, more rapid results

8. Iterative Test & Redesign  Repeat cycles of testing and reworking the system, subject to cost/time constraints  Focus on Functionality First !  Plan for several versions during development

9. Updates & Maintenance  In-the-field feedback, telemetry, user data, logs, surveys, etc.  Analyze and make iterative redesign/test recommendations  Updates and maintenance plan as part of the design!

UCD: 9 Step Overview 1.Define the Context 2.Describe the User 3.Task Analysis 4.Function Allocation 5.System Layout / Basic Design 6.Mockups & Prototypes 7.Pilot Tests & Usability Testing 8.Iterative Test & Redesign 9.Updates & Maintenance

UCD: Focusing Your Efforts  There are real-world constraints  Cutting out steps is not the way to economize!  Optimize the efficiency of each step  Here: Focus on the context and the user, to get the most value for the time spent

Concepts, Principles, Guidelines  No “cookbooks” (sorry!)  No simple, universal checklists  Think from perspective of user  There are many concepts, principles, and guidelines to help you  Focus on higher level principles that apply across situations, display types, etc.

Summary  Humans will use your system  Considering their many attributes, abilities, and limitations will lead to a better design  It’s not just common sense!  Human Factors is the study of how our “human factors” affect design  User Centered Design is a philosophy and a process to help designers sort it all out  It matters! And it ain’t easy!  Practice makes better (never perfect!)