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.
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Quality Assurance Statement
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Technical Report Documentation Page
1. Report No. FHWA-HOP-08-038 |
2. Government Accession No. |
3. Recipient's Catalog No. |
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4. Title and Subtitle Data Quality White Paper |
5. Report Date June 2008 |
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| 6. Performing Organization Code | ||||||
7. Author(s) Kyoungho Ahn(1), Hesham Rakha(1), and David Hill(2) |
8. Performing Organization Report No. |
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9. Performing Organization Name and Address Virginia Tech Transportation Institute FreeAhead Inc. |
10. Work Unit No. |
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11. Contract or Grant No. DTFH61-06-D-00004 |
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12. Sponsoring Agency Name and Address Federal Highway Administration |
13. Type of Report and Period Covered Interim Report |
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14. Sponsoring Agency Code
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15. Supplementary Notes Performed under subcontract to Cambridge Systematics Inc. (Task Order CA04-029) |
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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. |
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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 |
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19. Security Classif. (of this report) Unclassified |
20. Security Classif. (of this page) Unclassified |
21. No of Pages 47 |
22. Price
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Form DOT F 1700.7 (8-72) Reproduction of completed pages authorized
Metric Conversion Factors
(International System of 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 |
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| 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 |
| 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) |
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| 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 |
