WebWeb--Sites Evaluation Sites Evaluation Through EyeThrough Eye--Movements Movements
InvestigationInvestigation
Francesco MaringelliSensoMotoric Instruments GmbH – Teltow/Berlin (Germany)
International School for Advanced Studies, Cognitive Neuroscience Sector – Trieste (Italy)
GIMO2000 GIMO2000 -- PaviaPavia
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
To write for the web is different than to write for other types of media. Following, we will analyze differences between:
Print – WebTV – WebGUI - Web
WebWeb--Design and Evaluation:Design and Evaluation:BackgroundBackground
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
Print - Web• Speed (very fast/quite
slow)• Dimensionality (2-D/N-D)• Navigation
(limited/unlimited)• Canvas size (large/small)• Image quality (High/low)• Multimedia (low/high)• Interactivity (low/high)
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
TV – Web• Screen Resolution
(relatively poor/potentially reach)
• Input information (low/high)
• Viewing distance (far/close)• User posture
(relaxed/upright)• Nr. of users at the same
site/time (social/solitary)• User engagement
(passive/active)
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
GUI - Web• Control over actual
layout (high/low)• Difference in display
area (factor of 6/ factor of 100)
• Navigation control (high/low)
• “Integration” (single/multiple and part/whole)
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
Currently, there are a number of different approaches to Web design evaluation.
It is possible to assign them to two large and broadly different classes:
Subjective Evaluation (self-report, expert evaluation, role-playing, …)
Objective Evaluation (video-tapes, mouse rec., eye-movement rec., …)
WebWeb--Design and Evaluation:Design and Evaluation:State of the ArtState of the Art
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• Expert Evaluation (knowledge-based review by usability expert);
• Informal Developer Walkthrough(unstructured review by developers);
• Heuristic Evaluation (Nielsen and Norman, unstructured review of interface design done by trained evaluators);
Subjective MethodsSubjective Methods
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• Cognitive Walkthrough (Lewis and Polson, structured group walkthrough of design, post-hoc analysis based on cognitive theories)
• Pluralistic Usability Walkthrough (Bias, users, developers, and experts walkthrough in user role, action recording, discussion)
• Joint Design Walkthrough (Also called “paper prototype testing”, Developers and users evaluation group)
• Collaborative Usability Inspection (Costantineand Lockwood, Structured review of web-siteusability)
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• Mouse-click recording and analysis(dedicated software able to keep track of mouse movements and mouse selections)
• Video-tapes recording and analysis(simple recording of users behavior, to be analyzed through video play-back)
• Eye-tracking recording and analysis (eye-movements recording, then analysis)
Objective MethodsObjective Methods
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• There are a few available examples of Web-design evaluation through eye-tracking research, although there is a growing interest in this approach.
• The main advantage of such a technique is the possibility to map out how Web surfers really interact with a site, greatly limiting biases and errors due to both self-reports and observation approaches.
WebWeb--Design Evaluation Through EyeDesign Evaluation Through Eye--Movements AnalysisMovements Analysis
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• The Stanford-Poynter study was the first investigation trying to document which way 67 recruited volunteers read on-line newspaper.
• Results from this study, according to the Authors, are not congruent with current web-design guidelines.
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
Results
• Text seemed more attracting than photos or graphics.
• Banner advertisements do catch readers’ attention.
• Graphics other than banners were looked about 22 % of the time.
• Online news readers read shallow but wide, while at the same time pursuing selected topics in depth.
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
Reading behaviorCognitive workloadLevel of attention
Viewers entry pointLevel of frustration
Authors concluded that Eye-Movements analysis gave them highly relevant data,
otherwise not collectable, such us:
Web Web -- Sites Evaluation Through EyeSites Evaluation Through Eye--Movements InvestigationMovements Investigation
• Nowadays, only descriptive studies are available.
• Lack of a theoretical model within which to interpret the data and be able to make predictions.
• Eye-trackers are not currently supported by any internet browser – off-line, manual analysis of data is required.
Current Limitation of Web-Evaluation through Eye-Movements Analysis