What is Interaction Design? “ …designing interactive products to support people in their everyday and working lives. ” (Preece, Rogers, and Sharp – 2002) A multidisciplinary pursuit: –Anthropology –Computer Science –Cognitive Psychology –Engineering –Ergonomics –Graphic arts –Sociology A Little Bit of History… –Cards, flip switches, terminals, tablets/pucks, mice, windows, web… This includes services! You were born here

Good and Poor ID Important considerations –Who will use the system? –Why will they use the system? –Where will they use it? –What sorts of actions will they take? Example: in-car navigation system –Who: Owner or Renter? –Why: I want the fastest route, or I ’ m lost? –Where: Home or Abroad? –What: How do I avoid jams, or Where am I? Should there be just one ID for all of these?

What is usability? An Operational Definition –Efficient –Effective –Safe –Easy To learn To remember To use –Productive But also –Satisfying –Enjoyable –Pleasing –Motivating –Fulfilling

Forms of ID Guidance There are many “ shoulds ” and “ shouldn ’ ts ” –Separate the Save and Quit buttons –Adjust button size to navigation speed –Work for 10-minute learning time –Miller ’ s Magical number 7 +/- 2 But such rules all have important exceptions By studying principles of cognitive psychology we will develop a framework for design, rather than a list of guidelines

How to evaluate an interactive system Like any system, evaluation with respect to system requirements is crucial –and the interaction design should have been included in the system requirements! Most interactive systems are almost untested! When systems are tested, it is usually through subjective and qualitative evaluation –a good start, but not enough We will learn both qualitative and quantitative evaluation methods so that usability of the ID can be determined before the product has left development

The Process of Interaction Design Design of any sort is a creative process Before addressing the underpinnings of user interface psychology, it is useful to consider the practical elements We will focus on integrating ID/HCI into software/systems engineering

What is Interaction Design About? “ [Design is] a plan or scheme conceived in the mind and intended for subsequent execution. ” Oxford English Dictionary All designs must balance a variety of constraints and needs In ID, we especially focus on the concerns and needs of the user; a plan informed by –Intended use –Target domain –Practical considerations Alternatives must be evaluated –We have to discipline ourselves to generate alternatives!

The Five Basic Activities of ID Identifying needs, establishing requirements –Who are target users? What do they want? Need? Developing alternative designs –Conceptual and Physical design alternatives Building interactive prototypes –For users to participate, we need interactive prototypes Evaluating designs –Using prototypes Qualitative and quantitative product testing

Three Key Characteristics of ID The Interactive Design process should –Focus on users Sometimes called “ User Centered Design ” –Identify specific usability goals Agreed to and documented Help choose between alternatives and measure progress –Use iteration to engage users in the design process Iterative design with user involvement helps ensure suitability Also helps achieve “ buy in ” from user community

Who are the Users? Often different than “ customers ” Three categories can be identified: –Primary Frequent hands-on users of the system –Secondary Occasional users, or who use it through an intermediary –Tertiary Those who are affected by the system without having direct or indirect interaction with it Grocery store example

What are Stakeholders? They have a stake in the development “ people or organizations who will be affected by the system and who have a direct or indirect influence on the system requirements ” Users are a subset of Stakeholders, and so are Customers It is worthwhile to try to identify the stakeholders, though you will focus on users

Our Mission This semester you will execute this process in order to –Put the theory into action –Gain appreciation for the challenges and benefits –Begin to develop your own spin This week your group should work to identify and characterize your project’s users