Human Computer Interaction S. Camille Peres, Ph. D. peressc@uhcl.edu Outline • Human Computer Interaction • Articles from students • Presentation – User Centered Design – Human Computer Interaction Human Computer Interaction • Usability – Application of what we know about capabilities and constraints of the human to build computer interfaces that are ―easy to use‖ or ―intuitive‖ • Scientific Inquiry – Observing how humans interact with computers to test and develop theories regarding how humans process information. HCI lecture 2005.02.22 1 Articles • BRIEF summary of – What you found – Why it was interesting to you Usability • What does that mean anyway?! • People can easily, safely and efficiently do what they need/want to do. – Mechanical: chemical plant operations – Interface: VCRs, telephones, web sites • What about UHCL homepage? – Why would people come to this page? HCI lecture 2005.02.22 2 For Usability • Which page do you think is better? • Why? User centered design • Not unique to computers • Will use this paradigm and process to introduce – The theories and models of HCI and Psychology that apply to this process – Iterative process itself – How the process plays out with computer interfaces User Centered Design HCI lecture 2005.02.22 3 User centered design (from Mayhew, 1999) • Steps for any user centered design 1. Requirements analysis • What does the user do? • What does the user need? 2. Design/testing/development • How do you build the beast to meet the needs of the user? 3. Installation • Does the thing work the way it’s supposed to? User Centered Design 1. Requirements analysis • What does the user do? • What does the user need? These seem like obvious, intuitive questions, but are usually overlooked. • Wireless mouse – Why/when do we need a wireless mouse? • http://www.asmallertarget.net/2007/05/useless_technol.html User Centered Design > Requirements analysis Requirements analysis • Who is the user? – User profile • What does the user do? – Task analysis • What does the user need? – Information, tools, support from technology • These all lead to the definition of specific usability goals – addressing: can people easily, safely, and efficiently do what they need/want to do? User Centered Design > Requirements analysis HCI lecture 2005.02.22 4 Example: Gaming Industry • Who do we typically thing of? – Who’s missing? – Lucrative market possibility… • Family gaming – Who are the users? (User profile) – What do they do? (Task Analysis) – What do they need? (Constraints/Capabilities) User Centered Design > Requirements analysis Two options • Microsoft surface – Demo • Nintendo Wii – Family demo3 User Centered Design > Requirements analysis Psychology side bar Human processor Long Term Memory Working Memory Visual store (iconic memory) Eyes Perceptual processor Auditory store (echoic memory) Motoric processor Ears Cognitive Processor Fingers, etc. User Centered Design > Requirements analysis > Task Analysis HCI lecture 2005.02.22 5 Modeling (predicting) Human processing • GOMS (Card, Moran, and Newell, 1983) – Goals - what do you want to do? – Operators - tools that human processor has available (perception, cognition, motor response) – Methods - sequence of steps that use operators to accomplish goals – Selection rules - algorithm for choosing which method to use • Task analysis • GOMS will allow us to predict how long it will take someone to do a task. User Centered Design > Requirements analysis > Task Analysis Project Ernestine (Gray, John, & Atwood,1993) • Compare the work-times of telephone company toll and assistance operators on two different workstations – Needs analysis - what do the operators need to do? • Answer as many calls as accurately and quickly as possible. – How can the system be designed so operators can easily, safely and efficiently do what they need/want to do? • NYNEX was specifically interested in reducing the length of the calls. User Centered Design > Requirements analysis > Task Analysis GOMS modeling of task analysis • Contrary to expectations, GOMS predicted and the data confirmed, that performance with the proposed workstation was slower than with the current one. • This increase in performance time translated into a cost of almost $2 million dollars a year to NYNEX. • Scientifically, the GOMS models predicted performance with exceptional accuracy. User Centered Design > Requirements analysis > Task Analysis HCI lecture 2005.02.22 6 Example of GOMS KLM – Keystroke Level Modeling • To issue ―Bold‖ command – Select text • Using mouse • Using ―shift + arrow key’s‖ – Issue Bold command • Using mouse to click icon • Using keyboard shortcut Ctrl +B User Centered Design > Requirements analysis > Task Analysis KLM - Selecting text User Centered Design > Requirements analysis > Task Analysis KLM – Issuing Bold command User Centered Design > Requirements analysis > Task Analysis HCI lecture 2005.02.22 7 Time Parameters User Centered Design > Requirements analysis > Task Analysis {Back to user centered design} • Steps for user centered design – Requirements analysis • What does the user do? • What does the user need? – Design/testing/development • How do you build the beast to meet the needs of the user? User Centered Design > Design/testing/development Design, testing, & development • How do you build the beast to meet the needs of the user? – Should be based on findings from needs analysis – Iterative testing is integral to the success of this phase • Design • Test – Paper prototype, low fidelity testing, cognitive walkthrough, etc. • Redesign • Start over until goals are met! User Centered Design > Design/testing/development HCI lecture 2005.02.22 8 Example – Family Gaming • Prototypes – Fidelity—Low and medium • Testing – When should we do it? – Who to bring in? – What should they do? User Centered Design > Design/testing/development Psychology sidebar Eye tracking • Eye tracking and design guidelines – What are some design principles for good visual icons? – Eye tracking device can help identify which ones are better – Further, we can model this with cognitive architectures • ACT-R--a more sophisticated version of GOMS (Anderson, 1996) User Centered Design > Design/testing/development > Design For example • Fleetwood and Byrne (2002) compared visual gaze times for different icons • Properties of human processor can explain/predict results – Attention – Visual search processes – Among others User Centered Design > Design/testing/development > Design HCI lecture 2005.02.22 9 Examples of icons • Users would see one icon and then have to find that icon in a set of distracters. User Centered Design > Design/testing/development > Design {Back to user centered design} • Steps for user centered design – Requirements analysis • What does the user do? • What does the user need? – Design/testing/development • How do you build the beast to meet the needs of the user? – Installation • Does the thing work the way it’s supposed to? User Centered Design > Installation Installation • Does the thing work the way it’s supposed to? – More testing – Full fidelity user testing • What this is, what it isn’t. • How hard is it for the user to learn? – Immediately – To proficiency User Centered Design > Installation HCI lecture 2005.02.22 10 Back to our two options • Microsoft surface – Demo – Parody • Nintendo Wii – Family demo1, – Family demo2 – Family demo3 User Centered Design > Installation Psychology sidebar Expertise acquisition • With initial software programs – Hard to learn – People did not move beyond sufficient level of performance (Carroll & Rosson, 1987) • Then came GUI (Graphical user interface) – People learned faster – Do not progress to expert levels (Bhavnani & John, 1997; Lane, Napier, Peres, & Sandor, 2005) User Centered Design > Installation > Expertise Acquisition Expertise • What impacts whether users progress to efficient/expert levels of performance? – Overt training for efficiency (Bhavnani, 2001) – Observing others (Peres et al., 2005) – Differing motivations User Centered Design > Installation > Expertise Acquisition HCI lecture 2005.02.22 11 Next week • Learn about how behavioral issues can impact safety – Chris Montoressi • Human as an ―information processor‖ applies is these settings as well as HCI – Safety • Cell phones in cars • Response with a blow-out Psychology side bar Human processor Long Term Memory •Cognitive load •Automaticity Working Memory Visual store (iconic memory) Eyes Perceptual processor •Psychological refractory period Auditory store (echoic memory) Motoric processor Ears Cognitive Processor Fingers, etc. User Centered Design > Requirements analysis > Task Analysis Questions, comments HCI lecture 2005.02.22 12 References (1) Anderson, J. R. (1996). ACT: A simple theory of complex cognition. American Psychologist, 51, 355-365. Bhavnani, S. K., & John, B. E. (1997). From sufficient to efficient usage: An analysis of strategic knowledge. Paper presented at the SIGCHI conference on Human Factors in Computing Systems, Atlanta, GA. Bhavnani, S. K., Reif, F., & John, B. E. (2001). Beyond command knowledge: Identifying and teaching strategic knowledge for using complex computer applications. Paper presented at the SIGCHI conference on Human Factors in Computing Systems, Seattle, WA USA. Carroll, J. M., & Rosson, M. B. (1987). Paradox of the active user. In J. M. Carroll (Ed.), Interface thought: Cognitive aspects of human-computer interaction (pp. 80-111). Cambridge: Bradley Books. Gray, W. D., John, B. E., & Atwood, M. E. (1993). Project Ernestine: Validating a GOMS analysis for predicting and explaining real-world performance. Human-Computer Interaction, 8(3), 237-309. References (2) Fleetwood, M. D. & Byrne, M. D. (2002) Modeling icon search in ACT-R/PM. Cognitive Systems Research, 3, 25-33. Lane, D. M., Napier, H. A., Peres, S. C., & Sándor, A. (2005). The hidden costs of graphical user interfaces: The failure to make the transition from menus and icons tool bars to keyboard shortcuts. International Journal of Human Computer Interaction, 18(2), 133-144. Mayhew, Deborah (1999) The Usability Engineering Lifecycle--a Practioner’s handbook for user interface design. Morgan Kaufmann Peres, S. C. (2005). Software use in the workplace: A study of efficiency. Unpublished Dissertation, Rice University, Houston, Texas USA. Peres, S. C., Fleetwood, M. D., Tamborello II, F. P., Yang, M., & Paige-Smith, D. L. (2005, September 26 - 30). Pros, cons, and changing behavior: An application in using the keyboard to issue commands. Paper presented at the Human Factors and Ergonomics Society 49th Annual Meeting, Orlando, FL. Peres, S. C., Tamborello, F. P., II, Fleetwood, M. D., Chung, P., & Paige-Smith, D. L. (2004, September 20 - 24). Keyboard shortcut usage: The roles of social factors and computer experience. Paper presented at the Human Factors and Ergonomics Society 48th Annual Meeting, New Orleans, LA. HCI lecture 2005.02.22 13