Understanding driver/pedestrian conflicts: Driver Understanding driver/pedestrian conflicts: Driver behaviour and effects of measures at pedestrian behaviour and effects of measures at pedestrian

crossingscrossings

19th ICTCT Workshop in Minsk, Belarus19th ICTCT Workshop in Minsk, BelarusOctober 26thOctober 26th--27th 200627th 2006

Truls VaaTransportøkonomisk institutt (TØI), Box 6110 - Etterstad

N-0602 Oslo, Norge

2

ObjectivesObjectives

•• Describe the Describe the effects of road safety measureseffects of road safety measures especially especially addressed and designed to promote road safety for addressed and designed to promote road safety for pedestrianspedestrians

•• Discuss and Discuss and propose a theoretical explanationpropose a theoretical explanation why why ordinary pedestrian crossings seem to increase the ordinary pedestrian crossings seem to increase the number of accidents involving pedestrians at pedestrian number of accidents involving pedestrians at pedestrian crossingscrossings

•• Propose elements and dynamics in a suggested Propose elements and dynamics in a suggested ““Pedestrian Behaviour ModelPedestrian Behaviour Model””

3

Handbook of Road Safety Measures (2004)Handbook of Road Safety Measures (2004)

•• Marking pedestrian crossings on carriageways, normally Marking pedestrian crossings on carriageways, normally combined with traffic signscombined with traffic signs

•• Traffic signal control of pedestrian crossings (at intersectionsTraffic signal control of pedestrian crossings (at intersections and and midmid--block)block)

•• Raised pedestrian crossingsRaised pedestrian crossings•• Refuges (traffic islands on pedestrian crossings)Refuges (traffic islands on pedestrian crossings)•• Pedestrian guard railsPedestrian guard rails•• School crossing patrolsSchool crossing patrols•• pavement widening at intersectionspavement widening at intersections

• All: Estimates of effects on accidents by meta-analysis

4

Studies per 2004 (1997)Studies per 2004 (1997)•• Mackie and Older 1965 (Great Britain, ordinary and traffic signaMackie and Older 1965 (Great Britain, ordinary and traffic signal controlled pedestrian crossings)l controlled pedestrian crossings)•• Jacobs 1966 (Great Britain, pedestrian guard rails)Jacobs 1966 (Great Britain, pedestrian guard rails)•• Jacobs and Wilson 1967 (Great Britain, ordinary and traffic signJacobs and Wilson 1967 (Great Britain, ordinary and traffic signal controlled pedestrian crossings)al controlled pedestrian crossings)•• Wilson and Older 1970 (Great Britain, ordinary pedestrian crossiWilson and Older 1970 (Great Britain, ordinary pedestrian crossings)ngs)•• JJøørgensenrgensen and and RabaniRabani 1971 (Denmark, ordinary and traffic signal controlled pedestria1971 (Denmark, ordinary and traffic signal controlled pedestrian crossings)n crossings)•• Herms 1972 (USA, ordinary pedestrian crossings)Herms 1972 (USA, ordinary pedestrian crossings)•• LalaniLalani 1977 (Great Britain, refuges on pedestrian crossings)1977 (Great Britain, refuges on pedestrian crossings)•• Cameron and Milne 1978 (Australia, pedestrian crossings)Cameron and Milne 1978 (Australia, pedestrian crossings)•• InwoodInwood and Grayson 1979 (Great Britain, refuges on pedestrian crossingand Grayson 1979 (Great Britain, refuges on pedestrian crossings)s)•• Engel and Engel and KrandsgKrandsgåårdrd Thomsen, 1983 (Denmark, pavement widening and raised pedestrianThomsen, 1983 (Denmark, pavement widening and raised pedestrian crossings)crossings)•• Bagley 1985 (Great Britain, pedestrian guard rails)Bagley 1985 (Great Britain, pedestrian guard rails)•• YagarYagar 1986 (Canada, ordinary pedestrian crossings)1986 (Canada, ordinary pedestrian crossings)•• VodahlVodahl and and GiGiææverver 1986 (Norway, ordinary and traffic signal controlled pedestrian1986 (Norway, ordinary and traffic signal controlled pedestrian crossings)crossings)•• YagarYagar, , RopretRopret and Kaufman 1987 (Canada, ordinary pedestrian crossings)and Kaufman 1987 (Canada, ordinary pedestrian crossings)•• BoxallBoxall 1988 (Great Britain, school crossing patrols)1988 (Great Britain, school crossing patrols)•• EkmanEkman 1988 (Sweden, ordinary and traffic signal controlled pedestrian1988 (Sweden, ordinary and traffic signal controlled pedestrian crossings)crossings)•• Stewart 1988 (Great Britain, pedestrian guard rails)Stewart 1988 (Great Britain, pedestrian guard rails)•• Jones and Farmer 1988 (Great Britain, raised pedestrian crossingJones and Farmer 1988 (Great Britain, raised pedestrian crossings)s)•• Hunt and Griffiths 1989 (Great Britain, refuges on pedestrian crHunt and Griffiths 1989 (Great Britain, refuges on pedestrian crossings)ossings)•• Daly, McGrath and Van Daly, McGrath and Van EmstEmst 1991 (Great Britain, pedestrian crossings)1991 (Great Britain, pedestrian crossings)•• Downing, Downing, SayerSayer, , ZaheerZaheer--UlUl--IslamIslam 1993 (Pakistan, raised pedestrian crossings)1993 (Pakistan, raised pedestrian crossings)

5

Traffic control measures for pedestrians (I)Traffic control measures for pedestrians (I) Percentage change in the number of accidents Accident severity

Types of accident affected

Best estimate

95% Confidence

interval

Mid-block traffic signal controlled pedestrian crossings Injury accidents Pedestrian accidents -12 (-18; -4) Injury accidents Vehicle accidents -2 (-9; +5) Injury accidents All accidents -7 (-12; -2)

Pedestrian crossings with mixed phases at traffic signal controlled intersections Injury accidents Pedestrian accidents +8 (-1; +17) Injury accidents Vehicle accidents -12 (-21; -3) Injury accidents All accidents -1 (-7; +6)

Pedestrian crossings with separate phases at traffic signal controlled intersections Injury accidents Pedestrian accidents -29 (-40; -17) Injury accidents Vehicle accidents -18 (-27; -9) Injury accidents All accidents -22 (-29; -14)

6

Traffic control measures for pedestrians (II)Traffic control measures for pedestrians (II)Table 1: Traffic control measures for pedestrians with statistically significant effects on accidents. Percentage change in the number of accidents. (from: Elvik and Vaa, 2004). Percentage change in the number of accidents Accident severity

Types of accident affected

Best estimate

95% Confidence

interval Pedestrian guard rails

Injury accidents Pedestrian accidents -24 (-35; -11) Injury accidents Vehicle accidents -8 (-33; +27) Injury accidents All accidents -21 (-32; -9)

School crossing patrols Injury accidents Pedestrian accidents -35 (-67; +30)

Pavement widening at intersections or at pedestrian crossings Injury accidents All accidents -5 (-58; +117)

7

Traffic control measures for pedestrians (III)Traffic control measures for pedestrians (III)Table 1: Traffic control measures for pedestrians with statistically significant effects on accidents. Percentage change in the number of accidents. (from: Elvik and Vaa, 2004). Percentage change in the number of accidents Accident severity

Types of accident affected

Best estimate

95% Confidence

interval Raised pedestrian crossings

Injury accidents Pedestrian accidents -49 (-75; +3) Injury accidents Vehicle accidents -33 (-58; +6) Injury accidents All accidents -39 (-58; -10)

Refuges on pedestrian crossings Injury accidents Pedestrian accidents -18 (-30; -3) Injury accidents Vehicle accidents -9 (-20; +3) Injury accidents All accidents -13 (-21; -3)

Ordinary marked pedestrian crossings Injury accidents Pedestrian accidents +28 (+19; +39) Injury accidents Vehicle accidents +20 (+5; +38) Injury accidents All accidents +26 (+18; +35)

8

InIn--depth accident study depth accident study –– 36 accidents with pedestrians 36 accidents with pedestrians ((StatensStatens vegvesenvegvesen BuskerudBuskerud, 2001), 2001)

•• In 17 of the 36 accidents, the cause of the accident was attribuIn 17 of the 36 accidents, the cause of the accident was attributed to ted to pedestrian errorspedestrian errors

•• Pedestrians were hit by a car because they ran or Pedestrians were hit by a car because they ran or ““staggeredstaggered”” into into the roadway without forewarning the roadway without forewarning (!!)(!!)

•• Especially dangerous in combination with darkness and Especially dangerous in combination with darkness and obstructions of sightobstructions of sight

•• ““To see a car is not the same as the driver sees meTo see a car is not the same as the driver sees me””

•• In about 50% of the accidents, the pedestrian did not see the In about 50% of the accidents, the pedestrian did not see the vehicle.vehicle.

9

InIn--depth accident study depth accident study –– 36 accidents with pedestrians 36 accidents with pedestrians ((StatensStatens vegvesenvegvesen BuskerudBuskerud, 2001), 2001)

• The study is too small to conclude, but some observations may be used to state some hypotheses:

• Pedestrians involved in these accidents very often belonged to subgroups who are more exposed than the average Norwegian also in other contexts, i.e.:

• pedestrians often were impulsive adolescents, mentally disabled, children, elderly people, intoxicated….

10

InIn--depth accident study depth accident study –– 36 accidents with pedestrians (II)36 accidents with pedestrians (II)

• 24 of 36 accidents: Cause attributed to the drivers:

• Driving speeds were too high, and/or• “Too low awareness about risks although the circumstances called

for something different”.

• 28 of 36 accidents: Drivers did not see the pedestrians “before it was too late”

The two most pronounced explanations:

• 1) Drivers do not check blind spots when needed

• 2) Drivers are more directed towards the other road traffic than to spot pedestrians ((““looking for dangerslooking for dangers…………??””))

11

““too low awareness about risks although the circumstances too low awareness about risks although the circumstances called for something differentcalled for something different””

or simply that the drivers or simply that the drivers ““did not see the pedestrian before it was too latedid not see the pedestrian before it was too late””,,

The pedestrian Degree of

attentionInattentive Vigilant

Inattentive Problem At risk, but may be saved by the other

The driver

Vigilant At risk, but may be saved by the other

No problem

12

Refuge on pedestrian crossings Injury accidents Accidents with pedestrians -18 (-30; -3) Injury accidents Vehicle accidents -9 (-20; +3) Injury accidents All accidents -13 (-21; -3)

13

Raised pedestrian crossing Personal injury accidents Accidents with pedestrians -49 (-75; +3) Personal injury accidents Vehicle accidents -33 (-58; +6) Personal injury accidents All accidents -39 (-58; -10)

14

The message from the shape of a circle segment is:

”Caution, slow down! – otherwise a big jump of the car may follow” ((ConciousConcious processprocess?)?)

15

Trapeze-shaped crossing

”The smaller the ascending angle, the higherdriving speed I can tolerate” (Conscious?)(Conscious?)

16

Sinus-shaped crossing

”The lower the height, the higher driving speed I can tolerate” (Consci(Conscious?)ous?)

17

Ordinary pedestrian crossing Injury accidents Pedestrian accidents +28 (+19; +39) Injury accidents Vehicle accidents +20 (+5; +38) Injury accidents All accidents +26 (+18; +35)

18

””DescartesDescartes’’ Error: Emotion, Reason and the Human BrainError: Emotion, Reason and the Human Brain””((Damasio 1994):Damasio 1994):

•• AxiomAxiom:: Man’s deepest motive: SurvivalSurvival

• ���� We must have an organ, a risk monitorrisk monitor

for for detectingdetecting dangersdangers thatthat threaten survival

���� The body isis the risk monitor

EmotionsEmotions andand feelingsfeelings are the tools

Dangers must be experienced , dangers must be felt !

19

Ad hoc Ad hoc –– observations: Crossing/pedestrian ratiosobservations: Crossing/pedestrian ratios

•• LocationLocation City/City/villagevillage No of tripsNo of trips No of obsNo of obs RatioRatio•• OsloOslo citycity 1212 198 : 13198 : 13 15 : 115 : 1•• HHøønefossnefoss citycity 2828 703 : 28703 : 28 25 : 125 : 1•• SoknaSokna villagevillage 105105 314 : 9314 : 9 35 : 135 : 1•• BBæærumrum villagevillage 6666 355 : 6355 : 6 59 : 159 : 1•• KongsbergKongsberg citycity 1414 67 : 167 : 1 67 : 167 : 1•• RjukanRjukan citycity 2222 526 : 2526 : 2 263 : 1263 : 1•• ParisParis--NancyNancy--ColmarColmar--

•• DijonDijon-- ParisParis roundtriproundtrip 11 116 : 0116 : 0 116 : 0116 : 0

20

The problem: It is The problem: It is emptyempty most of the time most of the time

””NothingNothing happenshappens””

WhatWhat do do youyou learnlearn ??

AutomatedAutomated

21

Are Are pedestrianspedestrians threatsthreats for the drivers?for the drivers?

“….drivers are more directed towards the other road traffic than to spot pedestrians”

22

MC: 8 : 1MC: 8 : 1

LookingLooking for for dangersdangers ??

23

Thoughts about a Thoughts about a ““Pedestrian Behaviour ModelPedestrian Behaviour Model””• Maybe we need a “Pedestrian Behaviour Model”

• Being a pedestrian is “democratic”: No pre-selection – no “pedestrian licence”is required, everybody is allowed to enter “The system of pedestrians”

• Pedestrians exhibit greater variability in knowledge, understanding of traffic system, experience, competence, risk perception abilities…….

• Who should we design for? Which subgroup of pedestrians should be the “The dimensioning group of pedestrians”? Children? The elderly? The mentally disabled…..?

• The problem of impulsivity: Impulsivity “kills” monitoring of risk: From being part of a safe and secure behavioural system on the pavement – you may just jump into the street because you saw someone ….. (literally!)(literally!)

24

More thoughts More thoughts ……………………..• Crossing the street, looking left – right – left , assessing speeds of on-

coming vehicles, estimate the required time gaps to cross: Cognitively difficult

• “The relativity issue”: As pedestrian you are part of a slow-moving system, cars are moving (much) faster relatively to you: Cognitively difficult to get an overview of the system you are in

• Relativity (II): Being a “fast-moving driver in a system of cars” relatively to slow-moving pedestrians is much easier, pedestrians “seem more like constants” relatively to you”: To get an overview is much easier for a driver…

25

ConclusionsConclusions

1. Man’s deepest motive is survival (Damasio, 1994). The human organism is designed to primarily look for dangers. Drivers are looking for what they regard as threats to their survival, which predominantly are cars, not pedestrians

2. Drivers’ processing of information at ordinary pedestrian crossings, where pedestrians generally are infrequent, might be automated in such a way that no special attention is directed towards searching for pedestrians, because of the process of automation itself

3. Ordinary pedestrian crossing might be regarded as a trap where pedestrians falsely may feel they are safe while in fact they are not. Hence, this kind of pedestrian crossing should be removed or replaced by another type of crossing which has been confirmed to reduce the number of accidents.

4. (Updated meta-analysis will come…)