Crash resulting in incapacitating injuries

AADT

Annual average daily traffic

Adjustment factor

AIC

Akaike information criterion

Crash resulting in non-incapacitating injuries

BIC

Bayesian information criterion

Crash resulting in possible/non-evident injuries

Calibration factor

CMF

Crash modification factor

CURE

Cumulative residuals

DOT

Department of Transportation

Fatal + injury

HSM/HSM1

1st edition of the Highway Safety Manual

HSM2

2nd edition of the Highway Safety Manual

Crash involving a fatality

KABCO

Commonly used crash injury severity scale

MAD

Mean absolute deviation

MAE

Mean absolute error

MPO

Metropolitan planning organization

MSPE

Mean squared prediction error

Negative binomial

Crash resulting in no indication of injury or property damage-only crashes

OLS

Ordinary least squares

PDO

Property damage only

RMSE

Root mean square error

SPF

Safety performance function

TWLTL

Two-way left-turn lane

Calibration and Development of State-DOT-Specific Safety Performance Functions
2024

Download PDF

You must be logged in to download this publication.

Select Book Type

Paperback - $40.50
Ebook - $33.29

Buy the book

Request an exam or desk copy

Roadway safety management is a multi-step process that begins with screening a roadway network for sites with potential for safety improvement. Subsequent steps in the process include diagnosing safety problems at candidate sites, identifying countermeasures for implementation, conducting an economic appraisal of the countermeasures, prioritizing sites for safety improvement, and evaluating the safety effectiveness of countermeasure implementation.

NCHRP Synthesis 634: Calibration and Development of State-DOT-Specific Safety Performance Functions, from TRB's National Cooperative Highway Research Program, documents state departments of transportation practice on calibration factors and the development of jurisdiction-specific safety-performance functions.

Publication information

136 pages · 8.5 x 11 · paperback
ISBN Paperback: 0-309-71011-1
ISBN Ebook: 0-309-72433-3
DOI: https://doi.org/10.17226/27906

Suggested citation

National Academies of Sciences, Engineering, and Medicine. 2024. Calibration and Development of State-DOT-Specific Safety Performance Functions. Washington, DC: The National Academies Press.

Import this citation to:

Bibtext
EndNote
Reference manager

First Name
Last Name
Email (required)
I agree to receive emails from the National Academies (required)

We respect your privacy and will never share your information.

Search this publication

Front Matter i-x
Summary 1-4
1 Introduction 5-6
2 Literature Review 7-80
3 State of Practice 81-90
4 Case Examples 91-95
5 Conclusions 96-97
References 98-101
Key Acronyms and Abbreviations 102-102
Appendix A: Distributed Survey 103-112
Appendix B: Survey Responses 113-126

Log In

Former MyNAP users: You'll need to reset your password on your first login to MyAcademies. Click "Forgot password" below to receive a reset link via email. Having trouble? Visit our FAQ page to contact support.

Members of the National Academy of Sciences, National Academy of Engineering, or National Academy of Medicine should log in through their respective Academy portals.

Email (required)
Password (required)

Don't have an account?

Register

Email (required)
New password (required)
Retype password (required) Password must be at least 8 characters
I accept the terms of use
terms of use

Thank You

Thank you for creating a MyAcademies account!

Enjoy free access to thousands of National Academies' publications, a 10% discount off every purchase, and build your personal library.

Forgot Password

Enter the email address for your MyAcademies (formerly MyNAP) account to receive password reset instructions.

Email (required)

Reset Requested

We sent password reset instructions to your email . Follow the link in that email to create a new password. Didn't receive it? Check your spam folder or contact us for assistance.

Reset Password

New password (required)
Retype password (required) Password must be at least 8 characters

Reset Password

Your password has been reset.

Verify email

Verify Your Email Address

We sent a verification link to your email. Please check your inbox (and spam folder) and follow the link to verify your email address. If you did not receive the email, you can request a new verification link below

Calibration and Development of State-DOT-Specific Safety Performance Functions (2024)

Chapter: Key Acronyms and Abbreviations

Key Acronyms and Abbreviations

Publication information

Suggested citation

My Academies

Calibration and Development of State-DOT-Specific Safety Performance Functions (2024)

Chapter: Key Acronyms and Abbreviations

Key Acronyms and Abbreviations