Eye TrackingEye Tracking in the Design and in the Design and Evaluation of Digital LibrariesEvaluation of Digital Libraries

Bing Pan, PhD, Geri Gay, PhD, Helene Hembrooke, PhD, Laura Granka, Matt Feusner

HCI GroupDepartment of Communication and Information Science

Cornell Universityhttp://www.hci.cornell.edu

Eyes are Windows to Eyes are Windows to the Soul!the Soul!

Eye Tracking Eye Tracking ExperimentExperiment

ASL’s 504 commercial eye-tracker (Applied Science Technologies, Bedford, MA)

Eye Tracking MeasurementsEye Tracking Measurements

Micro-level of information processing– Fixation:

Indication of attention Intensive information processing during

fixations;

– Saccade: Indication of movement of attention Information processing is suppressed.

Eye Tracking ExampleEye Tracking Example

Fixations

Saccades

Scanpaths

Previous ResearchPrevious Research

Eyes are drawn to informative areas (Rayner, 1998);

Complex information leads to longer fixation duration; Fixation numbers are indication of importance of visual display (Fitts et al., 1950);

Difficult task leads to longer saccade (Takahashi et al., 2000);

Different tasks lead to different eye movement behavior (Hayhoe et al., 2002).

Study I: Eye Tracking Study I: Eye Tracking Research on Web PagesResearch on Web Pages

30 Subjects, 22 web pages from 11 most popular web sites from four categories (news, shopping, search, and business);

Half of subjects are asked to memorize the content;

30 seconds of viewings;Demographic data and recall were

measured.

Area of Interest (Lookzone) Area of Interest (Lookzone) AnalysisAnalysis

Where are the visually salient areas? Do people look at those?

Where do people look on a web page?

Illuminating visually salient areas...

Using illumination as another representation...

Study I Research Results Study I Research Results (under review):(under review):

– Males spent more time on fixations; females spent more time on saccades;

– The adjustment of people’s eye movement behavior on different pages;

– Complexity of web pages leads to complex scanpaths…

Study II. Eye Tracking in Study II. Eye Tracking in DL MetaTest ResearchDL MetaTest Research

How users of DLs use metadata and process metadata?– Test on three conditions:

Records with descriptions; Records with Metadata; Records with both descriptions and

metadata.

DL collections with descriptions…

DL collections with metadata…

DL collections with both descriptions and metadata…

Study II MetaTest Study II MetaTest Initial Results Initial Results

– Titles and sources are the mostly viewed metadata;

– The first few sentences in the description are read more carefully; the rest of them are skimmed;

– Before selection, a re-visit of the records for confirmation;

– Subjects focus on descriptions when both descriptions and metadata are on the same page.

Application in DL Design Application in DL Design and Evaluationand Evaluation

Which areas attract people’s attention? How can we capture their attention?

Which areas are left out by viewers’ eyes?

How can we design individualized interface?

How does their attention switch from one page to another?

What is the average scanpath on a web page?

ConclusionConclusion

Eye tracking can be a powerful tool in DL evaluations and usability testing;

Interface can be improved based on eye tracking results;

Comparison between alternative interfaces.

Future DirectionsFuture Directions

From information retrieval to learning community;

Will people use social navigation tools by attending to those social elements?

Testing the prototypes before actually spending money designing them.