traffic Evidence from changeblindness experiments Bertrand Sager Elisabeth Kreykenbohm Thomas M Spalek Simon Fraser University 2015 1 2 3 Introduction 1981 Hurt Ouellet ID: 347034
Download Presentation The PPT/PDF document "Conspicuity of motorcycles in" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Conspicuity of motorcycles in traffic: Evidence from change-blindness experiments
Bertrand SagerElisabeth KreykenbohmThomas M. SpalekSimon Fraser University(2015)
1Slide2
2Slide3
3Slide4
Introduction1981*
*Hurt, Ouellet, & Thom (1981)4Slide5
Typical Right-of-Way Violation
5Slide6
IntroductionCommon belief: Collisions are due to conspicuityMotorcycles are difficult to detect because they are small6Slide7
Countermeasures:Daytime running lights
Introduction
7
Then
NowSlide8
IntroductionCountermeasures:Headlight modulators8
Then
NowSlide9
IntroductionCountermeasures:Fluorescent jackets9
Then
NowSlide10
Does enhanced conspicuity reduce collisions?10Slide11
Does enhanced conspicuity reduce collisions?
*ACEM (2009)11
Motorcycle Collision
Types
Motorcycle Collisions: Multiple VehiclesSlide12
IntroductionIf motorcycle collisions are due to poor conspicuity,And if we have improved motorcycle conspicuity,Then why have failure-to-see collisions increased?Are these collisions really due to poor conspicuity?
Are motorcycles even inconspicuous?12Slide13
Change-BlindnessAre motorcycles less conspicuous than cars? Demo
13Slide14
14Slide15
15Slide16
Are motorcycles less conspicuous than cars?Change Blindness is a measure of attentionWe notice changes for attended objects
Change-Blindness16Slide17
Static Change-Blindness17Slide18
Static Change-Blindness18
95% Confidence Interval
Are
motorcycles
detected less frequently than
cars
?
Sager et al. (In Review)Slide19
Static Change-BlindnessDetection times 19
95% Confidence IntervalSlide20
Static Change-Blindness: DiscussionMotorcycles are visible:Higher detection rates than carsSimilar detection times to cars
20Slide21
ContrastSaliency (Sensory Conspicuity)21Slide22
OrientationSaliency (sensory conspicuity)22Slide23
Spatial FrequencySaliency (sensory conspicuity)
23Slide24
ColourSaliency (sensory conspicuity)24Slide25
Static Change-BlindnessSaliency maps and Gaze MapsSlide26
Perception is More than SensationContextIntentionMemory
26Slide27
Static Change-BlindnessCar and Motorcycle Gaze MapsSlide28
Static Change-Blindness: DiscussionMotorcycles are not invisible:Higher detection ratesSimilar detection timesSimilar gaze mapsSaliency maps do not predict gaze maps
Solving motorcycle collisions through conspicuityIs solving a problem that does not existAnd it is solving it the wrong way28Slide29
Dynamic Change-BlindnessBut these images were staticWhat happens when people actually drive?29Slide30
Dynamic Change-Blindness30Slide31
Dynamic Change-Blindness 1Ss Drove down a straight roadScreens flickered onceA parked vehicle was removedSs indicate change detection
31Slide32
Dynamic Change-Blindness 1
32
t
58
= 2.03
p
= .047
Motorcycles
are detected more frequently than
cars
95
%
Confidence IntervalSlide33
Ss Drove toward intersectionScreens flickered onceA vehicle was removed on half the trials(entering or exiting)(car or motorcycle)Ss indicate change detection
Dynamic Change-Blindness 2Slide34
SDT: Was ist das?34
Target presentTarget absentTarget reported Hit
False Alarm
Target not reported
Miss
Correct RejectionSlide35
Dynamic Change-Blindness 235
t40 = 3.48p = .001
t
40
= .24
p
= .81
95
%
Confidence IntervalSlide36
Dynamic Change-Blindness: DiscussionResults replicate findings from static change blindness experimentsMotorcycles are not invisible:Higher sensitivity for motorcycles than for cars
36Slide37
ConclusionMotorcycles are (very) visible.Why? Sensory conspicuity is not the issue.Efforts should be directed at education
Because the problem is likely a judgement issue37Slide38
Acknowledgments Daniel M. BernsteinFarhad D. DasturDavid J. FrocRAs
Dawn-Leah McDonaldJohn Dema-alaKevin SmithCarley WoodAndrew LoweryAmaris
TokJackie KingAaron Richardson
38Slide39
Questions?39Slide40
Additional SlidesSlide41
Braking Behaviour41Slide42
Additional Results 42
95% Confidence IntervalSlide43
Additional Results 43
95% Confidence IntervalSlide44
Additional Results 44
95% Confidence Interval