Chapter 6 The Process of Interaction Design By: Matt Bergstein Matt Bergstein Kevin Clark Kevin Clark Carol Lawson Carol Lawson Angelo Mitsopoulos Angelo Mitsopoulos Phil Townsend Phil Townsend

Introduction Intent of design is to develop a product that helps its users achieve their goals How can we do this? CH 1 expressed the importance of designing products which aid in everyday tasks CH 1 expressed the importance of designing products which aid in everyday tasks Begin by understanding the product (who needs it, how they will use it, where they will use it) How do we gain this knowledge? Involving the user throughout the process of design Involving the user throughout the process of design But what about innovative products where the user is less likely to envision its possibilities?

Goals of this Chapter Consider what ‘doing’ interaction design involves Ask and provide answers for some important questions about the interaction design process Introduce the idea of a lifecycle model to represent a set of activities and how they are related Describe some lifecycle models from software engineering and HCI and discuss how they relate to the process of interaction design Present a lifecycle model of interaction design

What is Interaction Design About? Fields of design Graphic design Graphic design Architectural design Architectural design Industrial and Software design Industrial and Software design Each has its own interpretation Oxford’s Def: “(design is) a plan or scheme conceived in the mind and intended for subsequent execution.” Designing therefore involves the development of such a plan or scheme, and for it to execute, it has to be informed with knowledge about its use and the target domain. (Ex: multi-level roads)

Interaction Design User-centered approach (users’ concerns direct development) Trade-offs and balancing (Ex: Road) Evaluation and alternate solutions Marc Rettig “To get a good idea, get lots of ideas” Brainstorming stimulates innovation

Communicating Interaction Design Communication is key Must express clearly to allow review, revision, and improvement Ways to communicate: Series of sketches (building plans) Series of sketches (building plans) Description in natural language Description in natural language Building prototypes Building prototypes

Four Basic Activities of Interaction Design (Intro) Identifying Needs and Establishing Requirements Who target users are and what are their needs Who target users are and what are their needs Developing Alternative Designs Conceptual Design – creating a conceptual model of what the product does Conceptual Design – creating a conceptual model of what the product does Physical Design – detail of the product (color, sound, images, menus) Physical Design – detail of the product (color, sound, images, menus) Building Interactive Versions of the Designs Allows user to actually interact (not specifically software vers) Allows user to actually interact (not specifically software vers) Ex: Paper-based (cheap, easy) Evaluating Designs Determining usability and acceptability Determining usability and acceptability

Three Characteristics of Interaction Design Process User Focus Center of attention in book’s entirety Center of attention in book’s entirety Center of Interaction Design Process Center of Interaction Design Process Specific Usability Criteria Specific usability and user experience goals set at beginning of project Specific usability and user experience goals set at beginning of project Help designers choose between alternative designs and check projects progress as developed Help designers choose between alternative designs and check projects progress as developedInteraction Allows designs to be refined based on feedback Allows designs to be refined based on feedback Takes time and must be repeated several times Takes time and must be repeated several times

Practical Issues Questions to be answered before interaction design: Who are the users? Who are the users? What do we mean by needs? What do we mean by needs? How do you generate alternative designs? How do you generate alternative designs? How do you choose among alternatives? How do you choose among alternatives?

Who Are The users? We need to find out the user’s requirements and needs Identifying users: User – the people who interact directly with the product to achieve a task User – the people who interact directly with the product to achieve a task Others? Others? Those who manage direct users, those who receive products from the system, those who test the system, those who make purchasing decisions, and those who use competitive products. (Holtzblatt and Jones 1993) Categories of user (Eason 1987): Primary – hands-on users of the system Primary – hands-on users of the system Secondary – occasional users Secondary – occasional users Tertiary – those affected by system or influence its purchase. Tertiary – those affected by system or influence its purchase.

Who Are The Users? Stakeholders – wide collection of people who all have a stake in the development of a successful product Includes: Development team and their managers Development team and their managers Direct users and their managers Direct users and their managers Recipients of the product’s output Recipients of the product’s output People who may lose their jobs because of the introduction of the new product People who may lose their jobs because of the introduction of the new productConclusion: Very wide range Very wide range Don’t include all of them Don’t include all of them Be aware of who you’re affecting Be aware of who you’re affecting

What Do We Mean By “Needs”? Not just “what do you need”? Approach: Characteristics and capabilities of users Characteristics and capabilities of users What they are trying to achieve What they are trying to achieve How they currently achieve it How they currently achieve it Would they achieve goals more effectively if supported different Would they achieve goals more effectively if supported different Target group must be consulted, not what you would like New innovations require cultural change in target population

How Do You Generate Alternative Designs? Common human tendency is to stick with something that we know works We end up overlooking good alternatives, which is a crucial step in the design process Where do alternative ideas come from? Cross-fertilization of ideas from different applications Cross-fertilization of ideas from different applications Evolution of an existing product through use and observation Evolution of an existing product through use and observation Straightforward copying of other, similar products Straightforward copying of other, similar products Therefore, it helps to deliberately seek out suitable sources of inspiration

Design Process Under some circumstances, the scope to consider alternative designs may be limited Design is a process of: balancing constraints balancing constraints constantly trading off one set of requirements with another constantly trading off one set of requirements with another drawing on the designers own experiences drawing on the designers own experiences The constraints may be such that there are very few viable alternatives available Upgrades to an existing system may or may not keep familiar elements

Design Examples: If designing a software system to run under the Windows operating system, then elements of the design will be prescribed because you must conform to the Windows “look and feel” and to other constraints intended to make Windows programs consistent for the user When designing the Windows 95 operating system to replace the Windows 3.1 and Windows for Workgroups 3.11 operating systems, the designers initially focused too much on consistency with the earlier versions (keeping familiar elements) For designing an electronic calendar, although many software- based applications already existed, paper-based books were a good source of inspiration (for the author of our text)

IDEO - A Box Full of Ideas IDEO, an international, innovative product design company, which has been involved in the development of many artifacts including the first commercial computer mouse and the PalmPilot V Uses a TechBox, which holds around 200 gizmos and interesting materials which are cataloged with more detailed information available via the TechBox’s online catalog Staff at IDEO take along a selection of items from the box to brainstorming meetings to be used as visual props or possible solutions to a particular issue When items become common place, they are removed from the TechBox to make way for the next generation of fascinating contraptions

Copying for Inspiration: Is It Legal? Copyright: covers the expression of an idea and not the idea itself covers the expression of an idea and not the idea itself is free and is automatically invested in the author of something, e.g., the writer of a book or a programmer who develops a program, unless they sign the copyright over to someone else is free and is automatically invested in the author of something, e.g., the writer of a book or a programmer who develops a program, unless they sign the copyright over to someone elsePatents: does protect the idea rather than just the expression of the idea does protect the idea rather than just the expression of the idea there are various forms, each of which is designed to allow the inventor the chance to capitalize on the idea there are various forms, each of which is designed to allow the inventor the chance to capitalize on the idea unusual for software to be patented, since it is a long, slow and expensive process unusual for software to be patented, since it is a long, slow and expensive process recent trend, however, towards patenting business processes (Amazon has patented its “one-click” purchasing process) recent trend, however, towards patenting business processes (Amazon has patented its “one-click” purchasing process) The dilemma comes in knowing when it’s OK to use someone else’s work as a source of inspiration and when you are infringing copyright or patent law

How Do You Choose Among Alterative Designs? Choosing among alternatives is about making decisions These decision are made by: Information gathered about users and their tasks Information gathered about users and their tasks The technical feasibility of the idea The technical feasibility of the idea Fall into two categories: Those about externally visible and measurable features Those about externally visible and measurable features Those about internal characteristics to the system Those about internal characteristics to the systemExamples?

Why We Concentrate On The External Factors? Our driving force is the way in which users interact with the product Therefore, we focus on visible and measurable behavior that affect this interaction Internal workings are important only to the extent to which they affect the external behavior The tasks that the user will perform should determine the design The tasks that the user will perform should determine the design Technical issues should take care of themselves Technical issues should take care of themselves

Choosing Between Alternatives – The User-centered Approach Let users and stakeholders interact with the product Discuss their experiences, preference, and suggestions Discuss their experiences, preference, and suggestions This process requires that: The designs are readily available that is reasonable evaluated by users The designs are readily available that is reasonable evaluated by users The process is free from technical jargon and complicated notations The process is free from technical jargon and complicated notations

Choosing Between Alternatives – Documentation Uses a description of how something will work or a diagram showing its components Downsides to this approach: Uses a static depiction for dynamic behavior Uses a static depiction for dynamic behavior Doesn’t communicate what the product will actually be like to the users Doesn’t communicate what the product will actually be like to the users

Choosing Between Alternatives – Prototyping Involves producing a limited version of the product in order to answer specific questions about the design and feasibility Used to overcome potential client misunderstandings and to test the technical feasibility of a suggested design and production Gives a better impression of the user interface than explanations There are various types of prototyping suitable depending on the stage of development and types of information needed

Choosing Between Alternatives – Quality Make a decision based on a perceived level of “quality” This process requires a clear understanding of what is meant by “quality” Downsides to this approach: People have different definitions of what quality is People have different definitions of what quality is People have different expectations for quality People have different expectations for quality Many projects have different stakeholder group, each who can define quality of a different way Many projects have different stakeholder group, each who can define quality of a different way A clear, concise definition of quality is rarely properly documented A clear, concise definition of quality is rarely properly documented

Usability Engineering The process of writing down formal, verifiable – and hence measurable – usability criteria is a key characteristic of an approach to interaction design called usability engineering This involves specifying quantifiable measures of product performance, documenting them in a usability specification, and assessing the product against them Example: This can be used to make changes to a previous version of a system based on feedback from results of usability tests This can be used to make changes to a previous version of a system based on feedback from results of usability tests

Lifecycle Models: Showing How The Activities Are Related A lifecycle model is used to capture a set of activities and how they are related More sophisticated models also incorporate a description when and how to move from one activity to the next More sophisticated models also incorporate a description when and how to move from one activity to the next They are popular because they allow for an overall view of the development effort so that progress can be tracked, deliverables specified, resources allocated, and targets set

Lifecycle Models cont’d No matter how complex, any lifecycle model is a simplified version of reality It is an abstraction that only includes that amount of detail needed for the task at hand Additional details will be needed to actually put a lifecycle model into practice Additional details will be needed to actually put a lifecycle model into practice Many different types of these models are available Some based on the software engineering and HCI models Some based on the software engineering and HCI models

A Simple Lifecycle Model For Interaction Design Please refer to the model on page 186 in Figure 6.7 This model incorporates iteration and encourages a user focus This model is not intended to be prescriptive It includes the following steps: Start with identifying needs and requirements Start with identifying needs and requirements Alternative designs are generated based on the requirements Alternative designs are generated based on the requirements Interactive versions of the designs are developed and evaluated Interactive versions of the designs are developed and evaluated The team gets feedback and determines whether or not to continue or iterate back The team gets feedback and determines whether or not to continue or iterate back The final product will emerge in an evolutionary fashion The final product will emerge in an evolutionary fashion This process may vary from product to product This process may vary from product to product

Lifecycle Models In Software Engineering Before the waterfall method was proposed in 1970, there was no agreed upon approach to software development. Since, many lifecycle models have come about: The waterfall The waterfall The Spiral The Spiral Rapid Applications Development (RAD) Rapid Applications Development (RAD) These were chosen to be discussed because they represent models used successfully in industry and they show how the emphasis in software development has gradually changed to include a more iterative, user- centered view.

The Waterfall Lifecycle Model First Known Model Linear Model Each step must be completed before moving on next step Each step must be completed before moving on next step Some feedback shown to be useful, but idea of iteration was not embedded in the model and the opportunity to review and evaluate with users was not built into this model.

Spiral Lifecycle Model Suggested by Barry Boehm, 1988 Two main features: Risk Analysis Risk Analysis Prototyping Prototyping Incorporates them in an iterative framework so that ideas and progress are repeatedly checked and evaluated. Explicitly encourages alternatives to be considered. Identifies and controls risk.

Spiral Lifecycle Model

Rapid Applications Development User-centered Minimized risk caused by requirement changing during the course of the project Two key features: Time-boxing: Time-limited cycles of approximately six months, at the end of which a system or partial system must be delivered. Time-boxing: Time-limited cycles of approximately six months, at the end of which a system or partial system must be delivered. JAD Workshops: (Joint Application Development) workshops where users and developers come together to thrash out the requirements of the system. JAD Workshops: (Joint Application Development) workshops where users and developers come together to thrash out the requirements of the system.

Rapid Applications Development Popularity of RADs has led to industry standard method called DSDM. Five phases to DSDM: Feasibility Study, Business study, functional model iteration, design and build iteration, and implementation.

Rapid Applications Development No order of activities. Activities are highly interconnected. Evaluation is central to model.

Usability Engineering Lifecycle Provides a holistic view of usability engineering and a detailed description of how to perform usability tasks Three tasks involved: Requirements Analysis Requirements Analysis Design/Testing/Development Design/Testing/Development Installation Installation Includes the style guide as a mechanism for capturing and disseminating the usability goals of the project