ITM 734 Introduction to Human Factors in Information Systems Cindy Corritore This material has been developed by Georgia Tech HCI faculty, and continues to evolve. Preece Ch 1 and 9.4

ITM 734 (Corritore)2 And we’re off! What is Human Computer Interaction  Can you define / describe it?

ITM 734 (Corritore)3 HCI HCI is at the interface between a human and a computer performing a task  Task - write document, calculate budget, solve equation, learn about Bosnia, drive home,...  Task might be work, play, learning, communicating, etc etc Essential user activities:  Express task (execution)  Interpret results (evaluation) Not just on the desktop! How many computers in your family home?

ITM 734 (Corritore)4 Why should we care? Computers (in one way or another) now affect every person in our society  Increasing % utilize computers at work and home –Tonight - count how many in your home/apt/room Goal – increase satisfaction, utility, efficiency, and safety Product success may depend on ease of use, not necessarily power  But not always – Macintosh OS vs. Microsoft Windows

ITM 734 (Corritore)5 Goals of HCI Allow users to carry out tasks  Safely (Three-mile Island, ATC)  Effectively  Efficiently  Enjoyably  With good utility  Ease of learning how to use  Rememberablitly (that is, easy to remember) Bottom line  Be invisible – highest compliment is no notice of the interface and the interaction (so natural)

ITM 734 (Corritore)6 What is difference between User-friendly interfaces and Programmer-friendly interfaces?

ITM 734 (Corritore)7 Famous Quotations “It is easy to make things hard. It is hard to make things easy.” (Al Chapanis, 1982) “Learning to use a computer system is like learning to use a parachute – if a person fails on the first try, odds are he won’t try again.” (anonymous)

ITM 734 (Corritore)8 Key Historical Events Design of the first Mac “The computer for the rest of us” Introduction of the web … just leave and go somewhere else

ITM 734 (Corritore)9 How Improve User Interfaces? Educate software professionals  Do NOT wait ‘til the end  Good UI can not be pasted on top of poorly- designed functionality Integrate UI design methods, techniques and knowledge into standard software development methodologies

ITM 734 (Corritore)10 UI Design / Develop Process NOT waterfall development (no iteration) NOT RAD (more limited user involvement) eXtreme Programming (iterative with users in strict timeframe)

ITM 734 (Corritore)11 UI Design / Develop Process User-Centered Design  Analyze user’s goals & tasks  Create design alternatives  Evaluate options  Implement prototype  Test - Evaluate  Refine  IMPLEMENT THE REAL SYSTEM  Be prepared for further iterative refinement

ITM 734 (Corritore)12 Preece process of ID Distills into four activities  Identifying needs and establishing requirements for the user experience  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 and the user experience that it offers

ITM 734 (Corritore)13 Keep in mind… 3 principles of user-centric design  Early focus on users and tasks  Empirical measurement  Iterative design

ITM 734 (Corritore)14 Know Thy Users! Physical & cognitive abilities & special needs Personality & culture Knowledge & skills Motivation Two Fatal Mistakes:  Assume all users are alike  Assume all users are like you –Please leave your ego at the door You Are Here

ITM 734 (Corritore)15 User Expectations (1) Some users expect the computer-based system to be just like the old system….

ITM 734 (Corritore)16 User Expectations (2) Other users expect the system to work magic…..

ITM 734 (Corritore)17 Design Evaluation Both subjective and objective metrics Some things we can measure  Time to learn  Speed of performance  Rate of errors by user  Retention over time  Subjective satisfaction