Interaction Design Principles

The Perfect User

• "The Perfect User" is a designer's idealized concept, embodying optimal user traits

Bad Designs

• Elevator controls and labels on the bottom row look similar, causing errors
• Top-row labels and buttons avoid the same mistake, indicating a design flaw in the bottom row

Good and Bad Design

• The TiVo remote is better than standard remotes due to its peanut shape, logical layout, color-coded buttons, and easy-to-locate buttons
• A good error box design should inform users of the error, but may discourage users
• A bad error box design may not have enough information or instructions/contact information to resolve the problem

Elements to Consider for Interaction Design

• The users
• What the activity is
• Where interaction occurs
• Optimize the interactions based on how users behave with the activity or product

Interaction Design Definitions

• Designing interactive products to support how people communicate and interact is the core of interaction design.
• Interaction design also includes the "design of spaces for human communication and interaction"

Interaction Design Goals

• Interaction design should develop usable products
• Usable products should be easy to learn, effective to use and enjoyable
• Interaction design also needs to involve users in the design process

Types of Design

• User interface, software, and user-centered design, product design, web design, and UX design are all types of design
• Interaction design covers all of these aspects as aspects of designing computer-based systems for people

HCI and Interaction Design

• Academic disciplines, design practices, and interdisciplinary fields relate to Human Computer Interaction (HCI) and interaction design
• Academic disciplines which contribute to interaction design include Psychology, Social Sciences, Computing Sciences, Engineering, Ergonomics and Informatics
• Design practices which contribute to interaction design include graphic, product, artist and industrial design, and film industry
• Interdisciplinary fields that 'do' interaction design are HCI, ubiquitous Computing, Human Factors, Cognitive Engineering, Cognitive Ergonomics, Computer Supported Co-operative Work and Information Systems

Multidisciplinary Teams

• Interaction design often involves multidisciplinary teams with diverse backgrounds
• Multidisciplinary teams lead to more diverse perspectives
• Multidisciplinary teams can benefit from more ideas and better designs
• A disadvantage of multidisciplinary teams is it can be difficult to communicate and design can be harder to progress

Interaction Design in Business

• There is an increasing number of Interaction Design (ID) consultancies
• Nielsen Norman Group helps companies design human-centered products and services
• Cooper supports research and product goal-related design –swim offers design services tailored to product development needs
• IDEO creates products, services, and environments delivering value to customers

Professionals in the ID Business

• Interaction designers deal with the design of interactive aspects of a product
• Usability engineers evaluate products using usability methods and principles
• Information architects deal with how to plan and structure interactive products
• User experience designers handle design and field studies to inform product design
• Product managers define problems to incorporate User eXperience (UX) design for business

User Experience

• The user experience is how a product behaves and is used by people
• One aspect of the user experience is the way people feel and are satisfied when using, looking at, holding or opening and closing something like a product.
• There is a user experience with every product that is used by someone from newspapers to reclining armchairs
• Aspects of the end-user's interaction with the company , its services and products are all par to the user experience
• One can only design for a user experience

iPod Example

• The quality user experience was part of its success from the start
• Its simple, elegant, distinct brand, pleasurable feel, and "must have" fashion status, made the iPod a success

Interaction Design Process

• Establishing requirements, developing alternatives, prototyping and evaluating are involved in the process of Interaction Design

Core Characteristics

• Users should be involved through the development of the project
• Specific usability and user experience goals need to be identified, clearly documented and agreed at the beginning of the project
• Iteration is needed in the core activities

Reason for Length

• To understand and design interactive products that fit with what people want, need, and may desire
• Everyone is different, no one size fits all
• Identify incorrect assumptions about user groups
• Be aware of people's sensitivities and their capabilities

What is Usability?

• Usability is a practical implementation of a good HCI
• Usability makes something easy to learn, effective to use, and enjoyable
• Usability is the effectiveness, efficiency, and satisfaction with which users achieve goals in an environment
• Usability applies to both hardware and software
• It is not about "is this product usable?", but rather bout "how usable is this product?"
• Usability is like oxygen as you don't notice it until it's missing

Poor Usability

• Comments such as "I really like it, but i dont use it much", "It's very fancy, but its not very useful", and "I find it a bit frustrating" all pertain to poor usability

Usability Goals

• Effectiveness, efficiency, safety, utility, learnability and memorability are all usability goals
• Being effective has to do with a system doing what it is supposed to do
• Being efficient has to do with a system supporting the user
• Being safe is how it protects the user from dangerous conditions or undesirable situations
• Good utility is the extent to which the system provides the right kind of functionality
• Easy to learn has to do with how easy a system is to learn to use
• Easy to remember is how easy a system is to remember how to use, once learned

Measuring Usability

• Effectiveness is measured by how good the system is
• Efficiency is measured by minimizing the steps to complete a task
• Safety is measured by how recoverable errors are and how little danger there is
• Utility is measured by if users can do what they need and want to do
• Learnability is how short the learning curve is. Ten minutes is standard for simple systems.
• Memorability is measured by how easy it is to remember what was once learned
• Satisfaction is measured by a subjective evaluation

Measuring Usability (cont.)

• The stress factor and discomfort affect Usability
• Easy of Perception affects usability
• Ease of Comprehension affects usability
• Level of Distraction affects usability
• A task performance measure includes task completion and response time rates

Findings on Usability Measures for a Website

• 95% of customers will be able to find and order a product
• 95% of physicians will be able to find, read, and understand the latest information on lung cancer treatments
• 95% of travelers will be able to make their own airline reservations
• All trained "service representatives" will be able to handle an average of 25 customer calls per hour

User Experience Goals

• User experience goals include aspects which are desirable, such as fun, helpfulness, and exciting or aspects which are undesirable, such as making something feel guilty, boring, or condescending

Usability and User Experience Goals

• Selecting terms to convey a person's feelings, emotions, can help designers understand the multifaceted nature of the user experience
• Trade-offs exist in how easy it is to measure usability goals versus user experience goals
• Trade-offs exist when product goals such as fun and safe conflict with one another

Design Principles

• Generalizable abstractions for thinking about different aspects of design
• Interaction design do's and don'ts
• Designers need to know what to provide at the interface
• Principles are derived from theory, experience, and common sense

Usability Principles

• Visibility, feedback, constraints, mapping, consistency, and affordance are aspects of usability principles

Visibility

• It should be visible what users need to do

Visibility Solutions

• Solutions include making the card reader more obvious; providing an auditory message and a label next to the reader

Feedback

• Sending information back to the user is feedback
• Feedback can include sound, highlighting, animation, and their combinations
• For example, a button which changes color and makes a noise to indicate the click

Constraints

• Constraints restrict possible actions
• Helps prevent incorrect options
• Physical objects such as keys are designed to constrain things

Logical or Ambiguous Design Examples

• Ambiguity exists with having trouble plugging in a mouse or keyboard
• It is not clear if the top or bottom connector is right
• Even color coded icons may not help the user
• Physical objects restrict movement

Design Them Logically

• Design can be improved with direct mapping of the icon and connector being adjacent
• Color coding helps associate connectors with their labels

Mapping

• Mapping is the relationship between controls, movements, and results in the world

Consistency

• Design interfaces so they have similar operations and use similar elements for similar tasks
• Use "ctrl" plus the first letter of the command. For example, ctrl+c is copy, ctrl+s is save

When Consistency Breaks Down

• When 2 commands start with the same letter
• When a user is required to learn multiple combinations of keys and make more errors
• Solutions can include ctrl+alt+S, ctrl+=+S

Internal and External Consistency

• Internal consistency is when designing operations act the same within an application
• It is difficult to achieve with complex interfaces
• External consistency is operations which act the same across applications and devices

Keypad Numbers Layout Inconsistency

• The lack of a standard keypad layout across devices is an example of external inconsistency

Affordances: to Give a Clue

• An attribute of an object indicates its use
• A mouse button indicates pushing, and a door handle indicates pulling
• Scrollbars and icons afford moving up and down, and clicking on
• In 1988, Norman used the term to discuss design of everyday object
• The term has been popularized when it comes to designing interfaces

Physical Affordances

• Everyday objects include cups, chairs, and doors

"Virtual Affordances" vs "Real Affordances"

• Interfaces lack physical object affordances
• He argued that it doesn't make sense to talk about real affordances in digital interfaces
• Interfaces are better as perceived affordances with Learned conventions of arbitrary mappings between action and effect at the interface and some mappings are better than others

Key Points Summary

• Interaction design pertains to designing interactive products to support the way we communicate and interact
• User-friendliness or design, is key when creating virtual stores
• Interaction design requires considering the context of use, type of activities, cultural differences, and user groups
• Furthermore, interaction design should have inputs from wide-reaching disciplines and fields