Table Of Content~------,
PBS0-121064
I
L!l~!lllllllllllllllllllllll
: . . . DOT HS-805 086
TRI-LEVEL STUDY OF THE CAUSES OF TRAffiC ACCIDENTS:
FINAL REPORT
Volume II: Special Analyses
J.R. Treat, N.S. Tumbas, S.T. McDonald, D. Shinar,
R.D. Hume, R.E. Mayer, R.L. Stansifer, N.J. Castellan
Institute for Research in Public Safety
Indiana University
400 East Seventh "street
Bloomington, Indiana 47401
Contract No. DOT Hs-034-3-535
Contract Amt. $1,531,466
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PRINTED MAY 1979
FINAL REPORT
u.s.
This document is available to the public through the
National Technical Information Service,
Springfield, Virginia 22161
Prepared For
U.S. DEPARTMENT DF TRANSPORTATION
National Highway Traffic Safety Admiolstr@tion _______
--~
'
Washington, D.C. 2D59D n~~-Rgg~~~~~~NT COMMERCE~'
OF.
1:
NATIONAL TECHNICAL
I INFORMATION SERVICE
,, · SPRINGFIELD, VA 22161
This document is disseminated under the sponsorship
of the Department of Transportation in the interest
of information exchange. The United States Govern
ment assumes no liability for its contents or use
thereof.
lECHNIC.t.i.. lfEPOJIT STANOAPO TITLE PAGf
.
1. Roport No. 2. Ga•ern111nl Ao:cu•ian Na. J. R•c•p•ent"a CGtolo~ No.
DOT HS 805 086 I~ •
•• Titlo '"'d $ubtitlo '· Report Ooto
Tri-Level Study of the CaUICI of TrafrJC Accidentl: FiDal Report. March 31 ,. 1977
(Volume 1: Caull&.l .fact(ir Tabulations and AIICIIincnts; d. Porlorioung OreonillliCifl Code
Volume II: Special Anilyses).
7, Aulhorld 8. Po•fo""i"t Orgo.,iiCifi ... Repou No.
J. R. Treat. N. S. Tilmbas, S. T. McDoDAld, o;· Shioar,
· DOT-HS-034-:3-S3S-77-TAC41
R. D. Hume, R. E. ~yer, R. L. Stansifer, N. J/Castellan
9, Porfo,..;,., Ora.,uotiio'ri'Nomo .., .. Addreu 10. lrorlo Unll Ho •.
llutitute for Research in Public Safety.
Indiana University II. Contract or Gronl No.
400 East Seventh Street DOT- HS-OJ4..3-S3S
T,.,..
Bloomington, Indiana 47401
13. of Rop~t """ Porioil Cnored
11. s,.,. •• ,,,., Ago.,cr Nomo .. oiul Addro .. Final Report
Ausust 1972-March 1977
U.S. Department of Tranaportation
National Highway Traffic Safety Administration J•. $pc111uco•int Agorcy Code
Washington, D.C. 20590
U. Supplo111entor, Hotu
Air•"••'
Jd.
Thil iathc Fillal Report of thc"Tri-Lcvcl St11dy oftbc CaUICt ofTraffJCAcciclenta,"pcrformed by the llldian& UDi~ty
IDnitute for llclcardl in Pub~ Saf'ety (IRPS), Wider coatract to the National Hi&hway TrafT'IC Safety Adm.idltration
(Contract No. DOT·H~J4-3-,3S). Several Interim aad lpCCia1 invcatiption rcporta hlll:vc bceD relcaacid previously.
'
~ ',
Volume I proYides c:au,aal result tabulatiom from PJwei II throuah V, aDd related analyaeo~ Volume II preentleveral
apecia1 analy•iJ reportS dealins with·driver viii on, knowledJe, peycholop:al make-up, etc. Phue I data differed in format,
aDd were preaented i.D ,a previoua report. ._",.,.,.__ , _ _, , '-: -, ·
--~....,_~// .~\"'" ,·,. ;;;· (
Data were collected on three Ievela o{dctail. Police reportl and o~r baseline data on the Monroe County, lndia.Da atudy
area were collected on Level A. On Level B, tcam1 or tcchniciau reepolldcd to accidcnu at the time of their oc:currcDCC to
conduct oo-accoe iove•tiptioo.t; a total oC2,258 invatiptio111 were conducted dlll'iq Phues Il throUJh V. CoDC\UTently,
429 of these 8Q:idents were independently examined by a mwtidilcipl.i.oacy team on Level C. Other apccialaurveya were
a.llo conducted.
One or more human facton wu cited by the iD-depth team ua probable cawe in 92.6% of accident& investipted in Phases
U through V. Environmental facton were cited u probable caues in 33.89(, of these accidmta, while vehicular facton were
identif'JCd U probable CIUiel in 126%, The major human direct alllllel were improper lookout, exceuivc &peed,
illattCDtion, improper cvuive action, aDd internal diatractio!L l...eadina eavironmental accident CI\JICS were view
obatruetiODJIU1d alic:k roads. The major vebicular caUIIel o{ IUicidcnta were brake failure, inadequate tread depth, Udc-to-
5tde brake imbalallce, uDder-inflation, ud vehK:Ie related viaion obltnlctiona.
Vision (capccial..ly poor, dynamic visual acuity) and pcnoll&lity (capccially poor pcnonal and soc:ial adjwtmcnt) were
foWid related to accident-involvement. However, u meuurcd in thia atudy, ltllowlcdae of the driviDI taak wu not ahown
to be related.
17. JC.,. ...... Dh•l..,tion Stat_.,.,
··~
Tratr~e accidcat cauacs; driver crron; roadway claip, main- Availability iJ unlimited. ~tl ~y be releued to the public
teaaDcc aud liiDiq; vehic:le dcfc:cta, mainlCIIaiii:C llld inlpection; tbro\llh the National Technical Ill(o rmation Service, Sprilllf'aeld,
driver vision testiaa; driver knowledp test; multidilciplinary cruh Viqi.aia 221Sl.
raearch.
s...,.,,,
19. Sea.ftt, Cl.oalf. (•I thle •.-rtJ 2G. Cln•ll. (al thbllot•l 2:. No. of P.,u 22.. Prie•
None None -311 /lltt- lf-¢1
c•·•••
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TRI-LEVEL STUDY OF THE CAUSES
' OF TRAFFIC ACCIDENTS: FINAL REPORT
VOLUME II .Special Analyses
·Report No. DOT-HS-034-3-535-77-TA C
Table of Contents
1.0 .Intr~uction: .......... : ...· .........•................... ; ... : ........ ·. ... ·. 1
1.1 Research Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Report Structure .................................. ; . . . . . . . . . . . . . . . . . . . . . 2
1.3 Status of Accident Investigation and Data Collection Activities ............ ·. . . 3
1.4 Background ......... ; ................. .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.01--D. river Attributes in Relation to Accident Involvement and Cau~atio~ ~: . -~~-:-:--·t1--~~
' . . ) . ·,_
2.1 Driver Vision Test ............................... , ..........., ............ 11 :_
2.1.1 M~thodological 'Approach ... : ...........' ................... ·. . . . . . . . 12
2:/.2 Objectives ............. : ............ ·. ........ ·. .... ::.·" .... ;:.,. ·.. ·. ·. ..... 13
2.1.3 Method ................ '· .................................... , ..... 14
2.1.3A The Vision Test ......... ·. .................... .' ............... 14
2.1.3.2 Subjects . ·, ................................................. 17
2.1.3.3 Driving Data .. _. ............................................ 17
2.1.4 Results and Discussion .......... -......... :; ....... : : . . . . . . . . . . . . . . . . 18
2.1.4.1 Introduction ... ·. ............................. ·. .............. 18
2. 1.4.2 Test-Retest Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.1.4.3 Additional Comments on the Individual Tests .. : ............... 21
2.1.4.4 Additional Measures of St~biiity .............................. 23
2.1.4.5 Practicality Assessments ..................................... 26
2.1.4.6 Validity Assessments ..... , . ·. .............. , .................. 30
2.1.5 Summary, Conclusions, and Recommendations .. : .. ·. ....... : ........... 37
2.2 Driver Knowledge ·Test ... : ...... ·. : ......... : ............................ 39
2.2.1 Introduction and Overview ...........- ........ :: .......... : ........... 39
2.2.2 Method .. : ....................... -......... .-. . . . . . . . . . . . . . . . . . . . . . . 40
2.2.3 Results and Discussion ... '. ......... ·. ...._ _ ............ : .......... ·.-·-.... -43
2.2.3.1 Age Analysis ..' : ... . -~- ...................................... 43
2.2.3.]: Sex Analysis . : .· ...... : ......... : . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
2.2.3.3 Driver Education Analysis .............................. :_ . . . . 45
2.2.3.4 Factor Analysis ............................. : . . . . . . . . . . . . . . . 45
2.2.3.5 Involvement Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
2.2.3.6 Error Analysis ·. ...................... : . . . . . . . . . . . . . . . . . . . . . . . 49
2:2.4 Conclusions and Recommendations .................................. 50
iii
2..3 Methodology Development: New Driver Measu~es ............. , ....... ~ ..... 51
2.3.1 Introduction -...... ·. ................ : : ..... .' ............ :·. . . . . . . . . . 51
2.3.2 Background . ·. ....................... ·. ..................... ·.· ......... 51
2.3.3 Independent Variables: Basic Human Traits and Characteristics . . . . . . . . . . 52
'2.3.4 Dependent Variables: Risk Taking, Poor' Decision Making, · '··
Poor Recognition and Poor Motor Sk.i/1 ....................' . :·: ........ 65
2.3.5 Resultant Plan for Future Research .......................··..l..\1· :,., .. . . . . . . 66
2.3.6 Preliminary Study (Study No. 1) .... :: ................... ~ .'. . . . . . . . . . 71
2.3.6.1 Methodology ·. :· ......... ·.· ... : .................... ::.......... 72
2.3.6.2 Results .............................................. ·.. . . . . 74
2.3.7 Validation Study (Study No. 2) ........................... ·: ......... 77
2.3.8 Supplemental Study Using In-Depth Interviews (Study No. 3) . . . . . . . . . . . 80
2.3.8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
2.3.8.2 Method ................................... , .. ':. :::·~......... 8'1
2.3.8.3 Results and Discussion .......................... : . ·.:. . . . . . . . . 81
2.3.8.4 Conclusions ..........................· .··. ........ ·.':' ........ :. · 85
2.4 Driver Characteristics and Culpability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
2.4.1 Relationships Between Age/ Sex and Driving Experience,
Vehicle Familiarity, Annual Mileage and·
Road Area Familiarity ........... ·. . '.' .................... /. . . . . . . . . . 86
2.4.2 Adjusting Driving Experience, Vehicle Familiarity, Annual Mileage
and Road Area Familiarity for Driver Age and Sex . . . . . . . . . . . . . . . . . . . . 90
2.4.3 Differences Between Culpable and Noncu/pable Drivers . . . . . . . . . . . . . . . . 90
3~0/~__Pecial Analyses: Human, Vehicular, and ~nVi_r?.,n;mental _
Characteristics. and Accident Causation }·/ :,·~. ........ : . ; : . : ,_.. . . . . . . . . . . . . . . . 105
3J Cluster Analysts ......................................... , .............. 105
3.1.1 Introduction ...................................................... 105
3.1.2 Cluster Structure at 8 Groups .•.......... , ............................ 107
3.1.3 The Dimensional Structure ofthe Eight Clusters ........ , ............... 109
3.1.4 Stability of the Cluster Structure Model-Comparison with
On-Site Cluster Analysis .......... ·. .......... : ............... , ....... 112
3.1.5 The Distribution of Other Variables on. the Clusters ..................... 113
3.1.6 Summary ........................... , .............. , .. -............. 120
3.2 AID Analysis ......... ~ ............ .' ... _. ................................... 120
3.2.1 Introduction ....................................................... 120
3.2.2 Afethodology ................ , ..................................... 121
· 3.2.3 Findings ....................., ............. : .... ·. ......... ·. .............. 122
3.2.4 Conclusions a~d Recommendations for Future Research ................. 153
iv
',
'4-.fl/Motorcyele Accidents and Causes : .' ....................................... 155
'";,' (' ',
4.1 Summary-of Results ...... ·. .... ·.1~.,.: •••••••••••••••••••••• .' ••• , ••••••••• ,, .155
4.1./ Differences Between Motorcy~l~, Accidents and Other . .
Traffic Accidents (1973 Indiana State Police Data) ............ , ........ 155
4.1.2 Representativeness of IRPS Motorcycle Sample ......., ................ 156
4.1.3 Motorcycle Accident Causes ........................................ 156
4.2 Detailed Discussion ........... : .......... ,' ......... , . . . . . . . . . . .. . . . . . . . . . 157
4.2.1 Differences Between Motorcycle Accidents and Other
Traffic Accidents (1973 Indiana State Police Data) ... , ................. 157
4.2.2 Representativeness of IRPS Motorcycle Sample ........ , .............. 158
4.2.3 Motorcycle Accident Causes ... : .................................... 16J
S.O General Discussion ..... .' .................................................. 173
5.1 Introduction · ..................................... , . ·, .. ; ...... ·: . . . . . . . . 173
5.2 Methodology Evaluation ............................ , . . . . . . . . . . . . . . . . . . . 174
5.2.1 Converging Operations ..................................... : ....... 174
5.2.2 The Causation Hierarchy .. , .......... , ............. ;, .............. 175
5.2.3 The Clinical Assessment Method ...................... ·;,, ............ 177
5.3 Human Fl!-ctors in Accident Causation ........................• . ........... 177
5.3.1 Driver.Errors .................................... ·. .................. 178
5.3.2 Interactions of Human Direct Causes with Other Factors ............... 180
5.3.3 Individual Differences in Accident Causation .................. ; ....... 182
5.4 Implications for the Future Research and Safety Program .................... 184
5.4.1 Vehicle Countermeasures ............: . ........ , .... , ........ ·. ....... 184
5.4.2 Environmental Countermeasures ..... , ..... , .... ·. .................. :. 185
5.4.3 Driver Improvement ............................................... 185
6.0 Summary, Conclusions and Recommendations . ·. .......................... 187
6.1 Volume I: Causal Factor Tabulations and Assessments ...................... 187
6.1.1 Section 3.0:· Causa/Result Tabulations ............. ; ..... ~ ........... 187
6. 1.2 Section 4.0: Trend Analysis Across Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
6.1.3 Section 5.0: Analysis of Accident Severity as a
Function of Accident Causation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
6.1.4 Section 6.0: Driver Conditions and States in Combination
' .
with Other Factors· ........................ , ......... , ...... ·: ..... , .. 196
•
6.1.5 Section 7.0: Analysis of Assessment Practices .... , ............ , ........ 197
6.1.6 Section 8.0: Level B vs. C Comparisons ... : .......................... 200
6.1.7 .Section 9.0: Representativeness of Study Samples and ·
· Study Area ........................................................ 203
· 6.2 Volume II: Special Analyses .................................... , ......... 206
v
60201 Section 200: Driver Attribut~s and Reliuionship to
Accident.Ca,usation oo o0o 206
0 0 0 0 0 0 0 0 0 0 0 0, 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0. 0 0 0 0 0
6020101 Section 201: Driver Vision Testing o o o o 206
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
6020102 Section 202: Driver Knowledge Testing ~ 208
O.o 0 0 0 0 0 o 0 0 0 0 0 0 0 0 0 0 0 0 0. 0
6o2olo3 Section 203: Methodology Development- '
New Driver Measures 209
0 0 0 0 0 0 0 0 0 -0 0 0 0 0 -0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
602;104 Section 2.4: Driver Characteristics and Culpability 211
o 0 0 0 :; 0 0 0 0 0 0 0
60202 Section 300: Special Analyses: Human, Vehicular,
and Environmental Characteristics in Accident Causation 212
0 0 0 ; 0 0 _ 0 ·0 0 0 0 0 0
6020201 Section 3.1: Cluster Analysis· 212
0°0 0 0 0 0, 0 0.0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 0 0. 0 0
6020202 Section 302: AID Analysis 213
0 0 0 0 0. 0 0 0 0 0 • 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0. 0
602.3 Section 400: Motorcycle Accidents and Causes ; -~- 214
0 ••• 0 •• 0. 0 0 •••• 0 •• 0 •••
References ,o 2J 7
0 ••••• 0 •• 0 0 0 0 0 0 0 0 0 0 0 .-0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 • 0 0 0 • 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 •
Appendix A: Scatter Plot Diagrams ~ A-1-A-I 6_
0 •• 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 0 0 0 0 0 0 • 0 0 : 0 0 0
Appendix B: Selected Error Patterns on the Central Angular Movement
(CAM) Test, and the Threshold Scored ... _-.. B-1
0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 0 0 0 • 0
Appendix C: Basic Demographic Questionnaire : C-1
0 ••• 0 0 0 • : 0 • 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 • 0
Appendix D: Driving Record Questionnaire o o. . o, D-1-D-2
0 0 0 0 •••• 0,. 0 0 0 0 0 0 0 0 0 0 0
Appendix E: Alcohol-Drug Use Questionnaire o: E-1
0. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Appendix F: Personal Adjustment Questionnaire. 0: . F-1
0 0 0 0 0 0 0 •• 0 •• 0 0 •• 0 0 0 • 0 0 • 0 0 0 0
Appendix G: Tests of Personal Adjustment G~l-G-4
0. 0 ••• 0. 0 0 0 0 •• 0 0 0 0 0. 0 0 0 0. 0. 0:
AppendiJ' H: Social Adjustment Questionnaire .. H-1-H-2
0 ••••••••••••••••••••• 0 .-
Appendix 1: ·Standardized Tests of Sociai Adjustment ..... , ............... 1-1-1-2
Appendix J: Impulsivity Questionnaire J-l
0 0 0. 0 •• 0 ••• 0 ••••••••••• 0. 0 0 ••• ; 0. 0 ••••
Appendix K: Tests of Impulsivity . oK-1-K-2
0 0 0 0 0 0 0. 0 ••••• 0 0 ·: •••••••••• 0 •• 0 •• 0 0
Appendix L: Test for Clerical Ability ........................ L-1
0 ••••••• 0 0 0 •• 0. 0
Appendix M: In~Depth Human Factors Form ....... : ............ M--1-M-26
0 •• 0. 0
Appendix N: 24-Page Driver Profile Score Questionnaire ........ N-1-N-26
0 •••• 0 •••
vi
TRI-LEVEL.STlJDY OF THE CAUSES
OF TRAFFIC ACCIDENTS: FINAL REPORT ..
.- ~ "" . I.
Volume II Special Analyses
Report No. DOT-HS-034-3-535-77-TAC
List of Tabie~ and Figures ·
Table t-1: Summary of Baseline Data Collected by IRPS ; ... ; . . . . . . . . . . 5
Table 1-2: Summary of Accidents.Investigated by IRPS Using
Tri-Level Methodology . . . . . . . . . . . . .. . . . .. .. . . . .. . . . . .. . . . . 6
Figure I -1: Multi-Level Concept ............................. : ..........' . 7
Figure 1-2: Multi-Level Accident Investigation Studies . . . . . . . . . . . . . . . . . . 9
Table 2-I: The Age Distributions of All Groups of Drivers
Administered the DVT ..................... : .............. 18
Table 2-2: ' Threshold Levels on the Physical and
Psychological Scales for All Tests of .
20
Static and Movement Acuity ... ~ ...........................
Table 2-3: Test-Retest Correiatiom and Standard Errors
Obtained by IRPS with Corresponding Correlations
Obtained by SOC ........................................ 21
Table 24: Partial Test-Retest Correlations Controlling for ·
Operator and Time of Day . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 2-5: Mean Performance Scores on the Test and ·
Retest Sessions, and T Values for the
Difference Between the Two ................. : ....... :": . . . . 2S
Table 2-6: Inter-Test Correlations for the DVT ........................ 27
Table 2-7: Factor Loadings of Each of the DVT
Measures on the Seven Rotated Factors .......... ; ........... 29
Table 2-8: Selected DVT Scores by Involvement Group . . . . . . . . . . . . . . . . . 32
Table 2-9: Selected DVT. Scores .by Error GrouR . . . . . . . . . . . . . . . . .. . . . . . . 34
Table 2-10: Contingency Tables for Involvement in Right
Angle (RA) and Rear End (RE) Accidents as
a Function of Vision Scores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 2-1 I:· In-Depth Human Factors Form
Driver Knowledge Questionnaire ....... , .. , ............. , . . 41
Table 2-12: Proportion Correct Response by DKT Question
for Drivers in Seven Age Groups ........................... , 44
Table 2~13: Proportion Correct Response by DICT.Questio~ · ·
for Males and Female~. by Seven Age Groups ...... , . ~ ..... , .. 46
vii
Table 2-14: Proportion Correct Response by DKT Question
for Drivers with Formal Training and Drivers . _ _.,
Without Training by Seven Age Groups ....... , .... , : ....... 47
Table 2-15: Proportion Correct Response by Driver Knowledge . ~,
Test (DKT) Question for Three Involvement
Groups ....................... ~ ....................... :··. . . 48
Tablt: 2-16: The Relationship Between Specific.Accident ·
Causes and Specif_ic Causal Factors . . . . . . . . . . . . . . . .. . . . . . . . . . 49
Table 2-17: Observable Human Characteristics Which M_ay
Distinguish Problem Drivers from General Drivers . . . . . . . . . . . 53
Table 2-18: · Development of Independent and
Dependent Variables .................. _. ......... : . . . . . . . . 67
Table 2-19: Mean Score for High Accident and No
A~cident Groupson 22 Tests .......................... : ... 75
Table. 2-20: Prediction of Group Membership of Validation
Sample Based on Discriminant Function of
Original Sample ............................· . . . . . . . . . . . . . 78
Table 2-21: Mean Score for Accident (3 or more) and Control
(No Accidents) Groups on 22 Tests ......................... 79
rable 2-22: _ Average Profile Score for Drivers Who Did
and Did Not Commit Human Errors ....................... 82
l'ablc 2-23: Average Profile Score by Type of
Error Committed .' ... ·. ........................ ·. . . . . . . .. . . . 83
fable 2-24: Average Profile Scores for Groups of privers.
Who Committed Specific Errors .... ~ . . . . . . . . . . . . . . . . . . . . . . 84
Figure 2-1: Average Driving Experience (in Months) by Age
and Sex for Accident-Involved Drivers . . . . . . . . . . . . . . . . . . . . . . 87
Figure 2-2: Average Vehicle ·Familiarity (Months Driving
Experience) by Age and Sex for. Accident-Involved
Drivers ................................................. 88
Figure 2-3: Average Annual Mileage by Age and Sex for
Acciderit~Involved Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Figure 2-4_: . Average Road Area Familiarity by Age and
Sex for Accident-Involved Drivers .......................... 91
Tabk 2-25: Comparison by Female, Culpable and Nonculpable
Accident-Involved Driver Distributions Before and
After Adjustment for Driver Age ........................ : . . 92
Table 2-26: Relative ImpQrtance of Variable Classes in
Discriminating Between Culpable and N onculpable
Female Accident-Involved Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . 93
viii
Description:TRI-LEVEL STUDY OF THE CAUSES OF TRAffiC ACCIDENTS: FINAL REPORT. Volume II: Special Analyses. J.R. Treat, N.S. Tumbas, S.T. McDonald, D. Shinar,. R.D. Hume, R.E. Mayer, R.L. Stansifer, N.J. Castellan. Institute for Research in Public Safety. Indiana University. 400 East Seventh "street.
