Gaze, Eye Tracking and Mouse Tracking. Human Computer Interaction Topic 1 - Design and Evaluation Student: Susan Möller Ferreira

Transcription

1 Gaze, Eye Tracking and Mouse Tracking Human Computer Interaction Topic 1 - Design and Evaluation Student: Susan Möller Ferreira

2 Eye Tracking and Mouse Tracking Both techniques can be use to identify users attention. Mouse-tracking - identify users attention while visiting a web site. Tools for usability evaluation. Mouse-tracking - Web Pages usability evaluation.

3 Eye-tracking Device for measuring eye positions and eye movements. Principal methods: Search coils - Uses an attachment to the eye, such as a special contact lens with an embedded mirror or magnetic field sensor, and measure the movement of the attachment. Provided extremely sensitive recordings of eye movement. Electrooculogram - Uses electrical potentials measured with contact electrodes placed near the eyes. Is most useful for measuring the rapid eye movements. Method of choice for measuring REM during sleep. Video recording - Non-contact method. Light, typically infrared, is reflected from the eye and sensed by a video camera or other specially designed optical sensor. Most popular. Preferred for being non-invasive and inexpensive.

4 Cost x sensitivity Method choice - should consider the cost and application. Most sensitive expensive requiring expertise to operate properly. Low cost useful for many applications easy to use Interpretation of the results - requires some expertise poorly calibrated system can produce erroneous data.

5 Application Commercial Commercial sector :web usability, advertising, sponsorship, package design and automotive engineering. Presenting a stimulus to a sample of consumers while an eye tracker is used to record the activity of the eye. Examples - websites, television programs, sporting events, films, commercials, magazines, newspapers, packages, shelf Displays, consumer systems (ATMs, checkout systems, kiosks), and software.

6 Application Research Web usability - Analyze user interaction, quantifying which sections of a webpage are read, quick looked at, or skipped/ignored. Psychology experiments - It provides concrete data that may reflect the cognitive states of individuals. Example: Compare the difference between the eye-movement of novice and experienced drivers. Compare the difference between and younger and elderly people in walking.

7 Limitations Measure changes in gaze direction not absolute gaze direction. Calibration procedure user looks at a point or series of points eye tracker records position. Calibrating the tool can be a very complex task. To track eye movements usually requires sophisticated calibrations and the results are not always acceptable. One of the serious problems we, as researchers, often face is that the tracker goes offcalibration gradually.

8 Limitations Consume lot of time for doing experiments Expensive Not easily accessible. Studies are regularly performed off line on laboratory settings Small number of users; Different behavior; Web usability not typical frequent visitors.

9 Internet Images

10 Internet Images

11 Mouse-Tracking Tool for monitoring and visualizing mouse movement activities on a website. Page space like coordinates x and y collect mouse position x and y X time. Very simple to apply

12 Relevance of Mouse-Tracking Previous Research shows (some with eye tracking): visitors move their mouse cursor according to their focus of attention. strong correlation involving eye and mouse movements while Web Browsing Can be use to predicting point of attention Intent interest

13 Some related scientific articles How mouse movement could indicate the way user interpreted information Design some mouse tracking systems: Enhanced Restricted Focus Viewer (ERFV) ; MouseTrack tool ; Simple Mouse Tracking Applied to evaluate user interaction and assist page design improving the page usability 2007 Analyze the patterns of coordination between users eye and mouse movements when scanning a web search results page Reveals 3 patterns of active mouse usage: following the eye vertically with the mouse; following the eye horizontally with the mouse; using the mouse to mark a promising result.

14 Internet tools OpenCube.com - Tool for mouse tracking. ClickTale.com - Tool for mouse tracking. Ojay - library. Mouse.js - Tracks mouse movements and provides mouseenter/mouseleave events

15 Advantages Mass deployed - large data collections. Reach typical users and first time visitors in their natural environment. Continuously test live sites, offering insight information as new sections are deployed. Transparent to the users - navigate as they would normally do.

16 Limitations Not all data offers consistent information - not all users use the mouse as a reading aid. Some patterns that help to identify users whose visual focus is not determined by the cursor. Webmaster - visual inspection throw the visualization tool. Don t work for all pages - might interfere with pages that do not conform to W3C standards or are heavily on scripting tools. Further research and experimentations is needed.

17 Visualization example Black balls shows the areas on the web site that have more activity.

18 Visualization example User s mouse track and ball represent the time the user spend in some parts of the web page.

19 Visualization example Mouse trajectory indicating reading behavior and hesitation in the menu area.

20 Visualization example The green balls represent the time the user spend in each region of the page, bigger balls indicate more time in that region.

21 Visualization example Path followed by the user in the web page. The user pointed with the mouse to one result, read the short summary but in the end decided to click in another result.