Revisitation Patternsand Disorientation
Eelco Herder
Session on Empirical StudiesABIS Workshop 2003
Karlsruhe
Research Partners
IntroductionPrediction of DisorientationDescription of Pilot Study
Experimental ResultsDiscussion
Revisitation Patterns and Disorientation
Presentation Overview
Becoming Disoriented in a Web Site
Introduction
Where am IHow did I come hereWhere can I go to
Due to•non-linear structure of web sites•lack of context information•unfamiliarity with site or domain
Symptoms
Context Information Prevents Disorientation
Contextual links•e.g. menus, indexes and site maps•define users’ spatial or temporal context•are needed to understand the site structure•differ from site to site
Associative links•embedded in the content•interlink semantically related concepts•do not expose the site structure
Contextual Navigation Support
IntroductionPrediction of Disorientation
Description of Pilot StudyExperimental Results
Discussion
Revisitation Patterns and Disorientation
Presentation Overview
Task Efficiency and DisorientationUsers may be exploring the site or looking for specific information.
Users that are exploring a site take some disorientation for granted, similar to tourists in a city center.
We want to find out when people perceive their sense of disorientation as a problem.
Navigation Patterns
Goal Directed Exploring
Site Graph and Navigation Graph
Prediction of Disorientation
Web sites are commonly modeled as directed graphs
User navigation paths can be seen as an overlay of the site graph
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Characteristics of User NavigationNavigation graphs describe browsing behavior
Path length and linearityRevisitation (cycles and clustering)
Analysis of navigation patterns helps in answering questions:
Is the user exploring or is he lost?Does the user understand the site structure?
Prediction of Disorientation
Revisitation and LostnessContradictory experimental results found in literature
P.A. SmithUsers who cannot find desired information are lost.Lostness measure based on number of revisits:the more revisits, the more likely the user is lost
J.E. McEneaneyWell-performing users return often to navigational landmarks.The more linear the path, the worse the performance
Prediction of Disorientation
IntroductionPrediction of Disorientation
Description of Pilot StudyExperimental Results on Revisitation
Discussion
Revisitation Patterns and Disorientation
Presentation Overview
Experimental Design (1)ObjectivesFind relations betweennavigation patterns and user satisfaction
Subjects30 randomly selected Dutch students(15 from Utrecht, 15 from Twente)
Session LengthComplete session lasted 2.5 hourNavigation session lasted only 40 minutes
Description of Pilot Study
Experimental Design (2)Data Gathering Methods
Questionnaires(motivational factors, expertise, evaluation)
Performance tests(working memory, spatial capacity, episodic memory)
Observation and interview
Thinking aloud protocols (recorded on tape)
Navigation data capturing (Scone)
Description of Pilot Study
Web Sites Used and Example TasksWhat are the definitions ofpersonal budget and financial goalas they are presentedwithin this website?
Calculate how much the real valueof £ 7.826 will decrease in 5 yearsgiven an annual inflation of 3%.
Description of Pilot Study
Access Tracking Software
Analysis software Graph Package
path visualizationssite metrics
navigation metricsinference methods Description of Pilot Study
A Navigation Graph
Description of Pilot Study
IntroductionPrediction of DisorientationDescription of Pilot StudyExperimental Results
Discussion
Revisitation Patterns and Disorientation
Presentation Overview
Experimental Results
Revisitation Patterns
Percentage of RevisitsAbout 40% for personal finance tasks,about 25% for browsing on Amazon
(Tauscher: revisitation rate of 58% on long term)
Use of Back Button•On average 9,2 % of navigation actions.•Large differences between sites (3,3 – 15,8 - 7,8)•User tendencies are comparable
Experimental Results
Revisitation: ‘I will find my way back later’Average Connected Distance (ACD)The expected length of the path betweenany connected two pages x and y in the navigation graph.
What Does It Mean?A higher ACD indicates that users will visit more pages before they return to a certain pageby a direct link, instead of by multiple clicks on the back button
ACD and working memory positively correlated
Experimental Results
ACD vs Number of Revisits
CONNECT
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VISI
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20 Rsq = 0,2399
‘I will find my way back later’ means less revisitation
Experimental Results
Return RateReturn rateThe average number of times that a user will revisit a page.
Calculated by averaging the number of visits on all pages that have been visited at least twice.
What Does It Mean?A higher return rate means that users returnto a specific set of pages, most likely with a specific goal in mind.
Experimental Results
ACD, Return Rate and Disorientation
People with high Average Connected Distance have low revisitation rates – and low back button rates
They also make more intensive use of landmarks (once a page is revisited once, they come back more often)
Intensive use of landmarks is negatively correlated with disorientation.
Experimental Results
Average Time Spent on PagesMedian View TimeThe average time a user spends on a page while browsing.
In contrast, the average view time is overly influenced by a small set of ‘high content’ pages.
Our FindingsUsers who feel disoriented, spend more time on pages while browsing.The correlation is not very strong, though.
IntroductionPrediction of DisorientationDescription of Pilot Study
Experimental ResultsDiscussion
Revisitation Patterns and Disorientation
Presentation Overview
Revisitation Patterns and Disorientation
Combined measures on user navigation help in predicting users becoming disoriented.
Revisitation patterns are more accurate thanthe amount of revisitation.
We are still far away from perfection.Most likely uncertainty cannot be eliminated completely.
Discussion
Leveraging LostnessEven with slightly imperfect prediction of disorientation it is still possible to offer adaptive navigation support.
Examples of adaptive contextual navigation aids:•personalized site maps•visualization of navigation history•direct guidance•link annotation
In order to do that, we must be able to distinguish between the various kinds of disorientation.
Discussion
Limitations of this Study
The site structure has not been taken into account, due to its complexity.We have evidence that the structure is an important factor.
We haven’t yet been able to analyze the relations between the various measures in detail. This will involve time-consuming visual analysis, combined with more specific tasks and more detailed evaluation.
Discussion
Revisitation Patterns and Disorientation
Time for Questions
email: [email protected]
Research Partners