The human in Human-Computer InteractionPaul van Schaik Professor of Psychology
Learning outcomes • Appreciate scope, relevance and applications • State some methods • State some models
The problem • Technology-centred system design • Non-design-focused marketing/communication • Human needs and capabilities not adequately addressed The solution • Apply psychological models and methods to understand and aid the design of human-computer interaction
Interaction components Interaction components Artefact Artefact Artefact Task Task Task Person Person Person Trait Trait Trait State State State Interaction experience Interaction consequences A framework Interaction components Interaction components adapted from Finneran and Zhang (2003)
Activity • On the following slides, which link from the home page will lead to the correct answer? • The questions are at the bottom of each page and keep changing) • Write down your answer for each slide
1 Give the name and telephone number of the Subject Librarian (Subject Information Team Leader) for Chemical Engineering.
2 What is the maximum number of pages that you can print in a single print job?
3 Give one reason why you may not be able to reserve a book in L&IS stock.
4 How would you go about getting access to 'Design and Applied Arts Index' if you are at home?
5 When did the library start taking the journal Modern History Review?
6 You have been given the following reference in a reading list. Hirst, David (1990). Saddam’s gift and his gamble. Guardian 6th August, p. 19. Using the L&IS site, where would you access this newspaper article?
7 Using the L&IS site, go to the official web site for the Acts of the UK Parliament. From what year are the Acts available?
8 What is the name of the Information Gateway for Art, Design, Architecture and Media?
9 Which resource found on the L&IS web site would you use to find REFERENCES to journal articles (not journal articles themselves) on Forensic Science?
10 What is the class number (shelfmark) of the following book? Bradley, Phil (2002). The advanced internet searcher’s handbook. 2nd ed. Library Association Publishing.
Answers • Contact information • Library Facilities • How to • Electronic Sources • The Catalogue • Electronic Sources • Guide to the Internet • Information for your subject area OR Guide to the Internet • Electronic Sources • The Catalogue
Web usability research ‘We can liken a Web site's user experience to the metaphorical chain that's no stronger than its weakest link. If any one usability attribute fails, the overall user experience is compromised and many users will fail. How can you ensure the quality of the total user experience? You need an integrated view of usability, from the user's perspective, and you need to develop the site through user-centred [emphasis added] design.’ (Nielsen, 2008) ‘Although the gains don't fall into traditional profit columns, there are clear arguments for improving usability of non-commercial websites and intranets. In one example, a state agency could get an ROI of 22,000% by fixing a basic usability problem.’ (Nielsen, 2007)
Outline • What is Human-Computer Interaction? • Models • Methods • Impact
What is Human-Computer Interaction (HCI)? ‘A discipline concerned with the design, evaluation and implementation of interactive computer systems for human [emphasis added] use and with the study surrounding them’ (ACM SIGCHI, 1992)
Psychological models in HCI (1) • Goals, Operators, Methods and Selection rules (Card, Moran & Newell, 1983) • Norman’s (1988) interaction model • Comprehension-based Linked model of Deliberate Search (Kitajima et al., 2000) Used in Cognitive Walkthrough for the Web to model and evaluate Web site usability (Blackmon et al., 2002, 2003, 2005)
Psychological models in HCI (2) • Model of interaction experience (Hassenzahl, 2003) • Three levels of processing in interaction experience (Norman, 2004) • Design rationale (Carroll, 1995) and design patterns (Zajicek, 2004) • Technology Acceptance Model (Davis, 1989) • Unified Theory of the Acceptance and Use of Technology (Venkatesh et al., 2003)
A success story John, B. & Kieras, D. (1996). Using GOMS for user interface design and evaluation: which technique? ACM Transactions on Computer-Human Interaction, 3(4), 287-319. GOMS models to evaluate the usability and steer the design of real-world applications, including • mouse-driven text editor • directory assistance workstation • space operations database system • CAD system for mechanical design • television control system • nuclear power plant operator’s associate • intelligent tutoring system • industrial scheduling system • CAD system for ergonomic design • telephone operator workstation
Activity • On the following slides, rate the web page • The questions are at the bottom of each page and keep changing) • Write down your answer for each slide as a number between 1 and 7
Modelling interaction experience with web sites Schaik, P. van & Ling, J. (2008). Modelling user experience with web sites: usability, hedonic value, beauty and goodness. Interacting with Computers, 20(3), 419-432.
Model of interaction experience Product features Presentation Interaction Content Functionality Perceived quality Hedonic: identification stimulation Pragmatic: usability Consequences Goodness Beauty Usage based on Hassenzahl (2003)
Task Measures • Information retrieval in one of four versions of an intranet site • Measures taken before and after task • Perceptions • Pragmatic quality (perception of usability) • Hedonic quality (pleasure) • Evaluations • Beauty • Goodness (overall quality) • Task performance • Speed, accuracy, mental effort, efficiency
Summary of results • Model predictions for Beauty and Goodness confirmed • Beauty is influenced by hedonic attributes • Goodness is influenced by both hedonic and pragmatic attributes as well as task performance and mental effort • Pragmatic quality becomes more influential with system use • Hedonic quality is more stable with experience of web-site use than pragmatic quality • Beauty is more stable than Goodness • Results support the case against first impression as a measure of success
The role of context in perceptions of the aesthetics of web pages over time Schaik, P. van & Ling, J. (2009). The role of context in perceptions of the aesthetics of web pages over time. International Journal of Human-Computer Studies, 67(1), 79-89.
Previous work • Previous research (Lindgaard et al., 2006; Tractinsky et al., 2006) studied test-users’ perceptions of home pages after a brief exposure (500ms or less) and after exposure of several seconds • However, these studies • did not present test users with a (task) context in which to make their judgements, • used web pages from various unrelated domains, • did not examine congruence of these perceptions with perceptions after system use, and • did not manipulate the aesthetic design of web pages or study the relationship between usability and aesthetic value
Hypotheses • Aesthetic perception of web pages in a particular domain presented with a context of use (mode of use) is different from that without context (Experiments 1 and 2) • Relatively attractive pages are rated higher than relatively unattractive pages, but this depends on context (Experiment 1) • ‘What is beautiful is usable’ (Experiment 2)
Task • Rating of web pages after controlled brief exposure • Rating of web pages after self-paced exposure Context • Goal mode • Action mode • No context (as in previous studies)
Task • Rating of web pages after controlled brief exposure • Rating of web pages after self-paced exposure • Information retrieval task • Rating of web pages after self-paced exposure Context - as in Experiment 1 • Goal mode • Action mode • No context
Summary of results (1) • Context increases the stability of judgements • from those after a brief exposure to those after self-paced exposure and • from those after self-paced exposure to those after site use • Overall, stability from rating after a brief exposure to after self-paced exposure was relatively low • However, stability from rating after self-paced exposure to after use was relatively high