Eye TrackingFEK Division Meeting
2014-10-23Hugo Guyader, Doktorand
I. Eye Tracking
II. FEK experiment
Eye TrackingFEK Division Meeting
Eye tracking enables researchers to analyze people’s visual attention reflected in their pattern of eye movements, called ‘gaze’, point of regard’ or ‘scapath’.
!It“measures the distance and angle of the reflection of infrared light from the center of the pupil to determine the point of fixation of the person”.
Wedel and Pieters, 2008
!Optical tracking cameras record the pupil center location and the infrared corneal reflection to measure the orientation of the eyes in the visual environment.
Duchowski, 2007
Eye tracking devices record someone’s gaze, composed of two salient eye movements tracked over time:
(1) saccades = rapid jumps of the eye to one location to another, (2) fixations = longer and still moments of the visual field.
Wedel and Pieters, 2008
!Dwell time = sum of fixations and saccades on objects of interests.
Eye Tracking
Devices
Stationary Eye Tracker e.g. Tobii
Eye Tracking Glasses (ECG) e.g. SMI
!
+ Analytical software
Eye Tracking
• Interactive role: eye tracker serves as an input device, which is used by visually mediated applications.
• Diagnostic role: eye tracker provides objective and quantitative evidence of the user’s visual and (overt) mental processes.
!!
Duchowski, 2007
Eye TrackingApplication
• In marketing: pro-active research method for: • choice and search behaviour, • print advertising, • public policy information and social marketing
information, • television commercials, • online usability and advertising, • reading tasks in survey design, • brand extension research, etc.
Wedel and Pieters, 2008
• But also in neuroscience (attention, brain structure); psychology (reading, scene perception, visual search, natural tasks, auditory processing and other information processing tasks); human factors (aviation, driving, visual inspection, sports); computer science (interactive system); ergonomics (design), ophtalmology, etc.
Duchowski, 2002
Research Applications
Scene Perception
Advertising
Web
Web
Marketing
Survey
Time Travel…
FEK Experiment
Convenience supermarket mock-up.
5 shelves: tomato sauce, kidney beans, coffee and softeners.
3 product alternatives: classic, ecological, or fair-trade.
Different variables: brand, price, packaging colors, labels, information displays, décor, etc.
FEK Experiment
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memorized&un*l&the&cashier&asks&for&it.&4.2. Half&of&the&par*cipants&were&primed&to&buy&organic&food&
5. The&par*cipant&enters&the&experiment&room&with&the&shopping&list.&!6. The&cashier&greets&the&par*cipant.&If&the&par*cipant&does¬&take&a&shopping&cart,&the&cashier&shows&them&
so&that&the&par*cipant&takes&one.&6.1. The&par*cipant&does¬&receive&further&informa*on&from&the&cashier&and&is&let&free&to&shop&for&as&long&as&
needed.&7. The&par*cipant&hands&over&the&shopped&items&to&the&cashier&who&asks&for&the&consumer&number&and&
takes&a&picture&of&the&items&next&to&the&numbered&survey.&7.1. The&par*cipant&exits&the&experiment&room.&The&experiment&is&over.&!
8. The&par*cipant&hands&over&the&eye3tracking&glasses.&The&recording&stops.&9. The&par*cipant&fills&in&a&second&survey&on&sustainable&behavior.
FEK Experiment
The same prices and product arrangement as they are at ICA Maxi were implemented (low-cost products on the bottom, high-quality products on the top of the shelf). The participants were also provided with a shopping cart. Objective: offer a shopping experience as close as possible to ICA supermarkets, but with a green servicescape. Items evoking countryside or agriculture were displayed around the shelves: plants, WWF posters, wood, a green carpet, wooden baskets, etc. The participants were asked to remember a "consumer number" to make them cognitively busy so that they act as normal as possible and to reduce the experimental bias. There were two different experimental conditions: a control group (46% of the respondents) and a primed group (54%). The difference between both conditions lays in the additional instructions provided to the primed group: "The person you do the shopping for is actually sustainable-oriented and prefer to eat organic food". The primed group is representative of “deep green” consumers who genuinely search for green products. !Video of the experiment: http://youtu.be/Mm0g8mVHffE.
Analyses
Results
Gaze Map
Results
Focus MapControl Group
The Focus Map shows what parts of the supermarket have been seen the most.
Primed Group
Results
Focus Map
Becomes clearer, the primed group had more and longer fixations. They spent more time looking at green product alternatives, the green pricetags and the information displays.
Resultscontrol group primed group
Fixation Time Average [ms]
0 20001000
Heat Maps
The information displays about classic, eco and fair-trade alternatives of coffee, below the shelf, are fixated longer for the primed group. They evaluate the alternative offers also using the green price tags that signal green products from the rest.
Resultscontrol group primed group
Fixation Time Average [ms]
0 20001000
Heat Maps
For consumers who actively search for green products (the primed group), a misleading color packaging for a classic softener made their choice process much longer. They still used the price difference between the eco-friendly softener and the other classic alternatives to identify the “true” green product.
Statistics
peripheral vision not enough servicescape visual field reduced inaccurate what measures to use? time experimental bias
Eye Trackingdrawbacks
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