Gazing the screens Using eye-tracking for evaluating visually complex TV programming Author: Amund Berg Supervisor: Frode Volden Gjøvik University College © 2007

2/19 Outline Introduction and background Experiment Results Questions

3/19 Introduction and background Gazing the screens - a part of TiDE- project Television is traditionally produced as a single stream of images New digital equipment enables the producers to create more complex TV graphics There is little knowledge of how complex TV graphics affects the viewers behavior

4/19 Introduction and background Eye tracking has proven to be a useful tool in a variety of areas Despite this, few have used it for studies on television

5/19 Research questions Is eye tracking suited for studies of viewer behavior? Er eyetracking egnet for studier av seeratferd? Does the amount of graphics in television affect viewer behavior? Påvirkes seeratferden av mengden grafikk på TV?

6/19 Outline Introduction and background Experiment Results Questions

7/19 Experimental setup 21 participants 3 different videos Total of 15 minutes Questionnaire with 37 questions

8/19 Stimuli material Three different videos used as stimuli material Increasing amount of graphics 1.Static banner 2.SMS chat 3.Stock and exchange tickers

9/19 Outline Introduction and background Experiment Results Questions

10/19 Results Out of 21 participants, up to 50% was excluded because of faulty data (poor calibration etc) 10 participants with valid data for all sets, were used in most of the following tests IncludedExcluded N%N% Set 11152,41047,6 Set 21361,9838,1 Set 31466,7733,3 All sets ok1047,61152,4 One set ok1676,2523,8

11/19 Fixations, saccades and blink Three different types of events: »Fixation – Pause over informative regions »Saccade – Rapid movement between fixations »Blink – A special case of fixations where the horizontal and vertical position of the gaze is zero

12/19 Fixations, saccades and blinks Number of fixations, saccades and blinks per second: –Fixations: 2,2 –Saccades: 1,7 –Blink: 1,0 No significant difference between the conditions

13/19 Fixations, saccades and blinks Average time spent on fixations, saccades and blinks: –Fixations: 265 ms –Saccades: 56 ms –Blink: 265 ms No significant difference between the conditions

14/19 Saccadic vector A saccadic vector is calculated using Euclidean distance This vector describes how far the eye moves in a saccade An average vector is calculated based on the total vector divided by total number of saccades

15/19 Saccade vector The average length of an saccade in pixels Average: 1. 74, , ,9 The difference between conditions are significant

16/19 Fixation frequency Divided the screen into different Area Of Interest (AOI) Count the fixations in each separate area and divide by the total number of fixations

17/19 Fixation frequency The amount of fixation on graphics versus fixations on the program Average: 1.48,2 % 2.43,8 % 3.30,7 % The difference between conditions are significant

18/19 Scanpath and heatmap Set 1 Set 2 Set 3

Questions?