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21st Century Operations Using 21st Century Technologies

Data Quality White Paper

Foreword

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names may appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

Technical Report Documentation Page

1. Report No.

FHWA-HOP-08-038

2. Government Accession No.

3. Recipient's Catalog No.

4. Title and Subtitle

Data Quality White Paper

5. Report Date

June 2008

6. Performing Organization Code

7. Author(s)

Kyoungho Ahn(1), Hesham Rakha(1), and David Hill(2)

8. Performing Organization Report No.

9. Performing Organization Name and Address

Virginia Tech Transportation Institute
3500 Transportation Research Plaza
Blacksburg, VA 24061

FreeAhead Inc.
268 Golden Woods Court
Great Falls, VA 22066

10. Work Unit No.

11. Contract or Grant No.

DTFH61-06-D-00004

12. Sponsoring Agency Name and Address

Federal Highway Administration
Office of Operations
1200 New Jersey Avenue, SE
Washington, DC 20590

13. Type of Report and Period Covered

Interim Report
August 2007 – June 2008

14. Sponsoring Agency Code

 

15. Supplementary Notes

Performed under subcontract to Cambridge Systematics Inc. (Task Order CA04-029)
Contracting Officer's Technical Representative (COTR) Mr. James Pol

16. Abstract

This paper looks at the issue of data quality within the context of transportation operations and management. The objective of this paper is to investigate data quality measures and how they are applied in existing systems. This paper explores the relevance of the data quality measures that were defined in a report entitled "Traffic Data Quality Measures" and presents an overview of the requirements for the implementation of a real-time information program.

Specifically, this paper focuses on the real-time travel information applications within six primary interfaces (traffic management information, maintenance and construction management, transit management and information, information service provider information, parking information, and emergency management information) and their associated applications as identified in the publication of "Interim Guidance on the Information Sharing Specifications and Data Exchange Formats for the Real-Time System Management Information Program".

The paper examined the quality of traffic data in existing real-time ATIS applications for both the public and private sector. The paper provides recommended data quality measures for three widely utilized traffic-related parameters, travel time, speed, and weather information. These recommendations were defined for each of the six data quality measures, accuracy, completeness, validity, timeliness, coverage, and accessibility.

17. Key Words

data quality, quality measures, real-time information program, accuracy, completeness, validity, timeliness, coverage, accessibility

18. Distribution Statement

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this page)

Unclassified

21. No of Pages

47

22. Price

 

Form DOT F 1700.7 (8-72)                                                                       Reproduction of completed pages authorized

 

Metric Conversion Factors
(International System of Units)

APPROXIMATE CONVERSIONS TO SI UNITS
SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

in

inches 25.4 millimeters mm

ft

feet 0.305 meters m

yd

yards 0.914 meters m

mi

miles 1.61 kilometers km

AREA

in2

square inches 645.2 square millimeters mm2

ft2

square feet 0.093 square meters m2

yd2

square yard 0.836 square meters m2

ac

acres 0.405 hectares ha

mi2

square miles 2.59 square kilometers km2

VOLUME

fl oz

fluid ounces 29.57 milliliters mL

gal

gallons 3.785 liters L

ft3

cubic feet 0.028 cubic meters m3

yd3

cubic yards 0.765 cubic meters m3

NOTE: volumes greater than 1000 L shall be shown in m3

MASS

oz

ounces 28.35 grams g

lb

pounds 0.454 kilograms kg

T

short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t")
TEMPERATURE (exact degrees)

oF

Fahrenheit

5 (F-32)/9
or (F-32)/1.8

Celsius oC

ILLUMINATION

fc

foot-candles 10.76 lux lx

fl

foot-Lamberts 3.426 candela/m2 cd/m2

FORCE and PRESSURE or STRESS

lbf

poundforce   4.45   newtons N

lbf/in2

poundforce per square inch 6.89 kilopascals kPa

 

APPROXIMATE CONVERSIONS FROM SI UNITS
SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

mm

millimeters

0.039

inches in

m

meters

3.28

feet ft

m

meters

1.09

yards yd

km

kilometers

0.621

miles mi

AREA

mm2

square millimeters

0.0016

square inches in2

m2

square meters

10.764

square feet ft2

m2

square meters

1.195

square yards yd2

ha

hectares

2.47

acres ac

km2

square kilometers

0.386

square miles mi2

VOLUME

mL

milliliters

0.034

fluid ounces fl oz

L

liters

0.264

gallons gal

m3

cubic meters

35.314

cubic feet ft3

m3

cubic meters

1.307

cubic yards yd3

MASS

g

grams

0.035

ounces oz

kg

kilograms

2.202

pounds lb

Mg (or "t")

megagrams (or "metric ton")

1.103

short tons (2000 lb) T

TEMPERATURE (exact degrees)

oC

Celsius 1.8C+32 Fahrenheit oF

ILLUMINATION

lx

lux

0.0929

foot-candles fc

cd/m2

candela/m2

0.2919

foot-Lamberts fl

FORCE and PRESSURE or STRESS

N

newtons 0.225 poundforce lbf

kPa

kilopascals

0.145

poundforce per square inch lbf/in2

 

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