00935370

Component

https://doi.org/10.3141/1804-03

http://scholar.google.com...ttle&publication_year=2002

The use of Global Positioning System (GPS) technologies has expanded to perform traffic data collection for transportation studies such as work zone studies. To generate reliable results from the data acquired by using GPS devices, it is necessary to investigate such factors as sample size requirements that may affect a specific study and to establish a consistent method for data collection. It has been confirmed that the Institute of Transportation Engineers' "Manual of Transportation Engineering Studies" usually underestimates the sample sizes for travel time and delay studies. However, the hybrid method developed by Quiroga and Darcy overestimates the sample sizes. A modified equation is presented to estimate the minimum sample sizes for collecting field data with GPS devices. Travel speed may be more stable and can be easily measured for travel time and delay studies. Stopped delay varies considerably at intersections, and the sample sizes depend to a large extent on the permitted errors. Work zone layout and construction activities will create variations in vehicle flow within the work zone. To estimate the sample size requirements, it is advisable to use the standard deviation to measure the data dispersion, and a minimum of three initial test runs is required. GPS devices with sufficient accuracy usually require 5 to 10 samples for travel time and delay studies and work zone studies. Stopped delay studies may require a large sample of up to 30 test runs.

This paper appears in Transportation Research Record No. 1804, Transportation Data and Information Technology Research.

English

p. 17-22

2002

Transportation Research Record

0309077303

Figures (8) ; References (6) ; Tables (1)

Data collection; Dispersion (Statistics); Global Positioning System; Standard deviation; Stopped time delays; Traffic data; Traffic delays; Traffic speed; Travel time; Work zones

Sample size; Test runs

Highways; Planning and Forecasting; I72: Traffic and Transport Planning

TRIS, TRB, ATRI

Dec 10 2003 12:00AM

• CLEANING OF MATCHED LICENSE PLATE DATA
• COMPARISON OF DISTANCE ESTIMATES FOR COMMODITY FLOW SURVEY: GREAT CIRCLE DISTANCE VERSUS NETWORK-BASED DISTANCES
• COSTS AND BENEFITS OF USING INTELLIGENT TRANSPORTATION SYSTEMS AS AN ALTERNATIVE DATA SOURCE: CASE STUDY
• DECISION SUPPORT SYSTEM FOR ADVANCED TRAFFIC MANAGEMENT THROUGH DATA FUSION
• DESIGN CHARACTERISTICS OF NATIONAL TRAVEL SURVEYS: INTERNATIONAL COMPARISON FOR 10 COUNTRIES
• DEVELOPMENT OF AN XML-BASED SPECIFICATION FOR TRAFFIC MODEL DATA EXCHANGE
• DYNAMIC CAMERA CALIBRATION IN SUPPORT OF INTELLIGENT TRANSPORTATION SYSTEMS
• EFFECT OF FIELD SETUP ON ACCURACY OF TRAFFIC DATA COLLECTION USING MACHINE VISION TECHNOLOGY
• EFFECTS OF AMBIENT LIGHT, CAMCORDER SETTINGS, AND AUTOMATED LICENSE PLATE READER SETTINGS ON PLATE TRANSCRIPTION RATES
• ENABLING AND MANAGING GREATER ACCESS TO TRANSPORT DATA THROUGH METADATA
• ESTIMATING TRAVEL TIME SUMMARY STATISTICS OF LARGER INTERVALS FROM SMALLER INTERVALS WITHOUT STORING INDIVIDUAL DATA
• INTEGRATED SIGN ORDERING SYSTEM THROUGH NETWORKING AND RULE BASE APPLICATIONS
• MEASURING VARIABILITY IN TRAFFIC CONDITIONS BY USING ARCHIVED TRAFFIC DATA
• MONTE CARLO SIMULATION IN SAMPLING TECHNIQUES OF TRAFFIC DATA COLLECTION
• OBJECT-ORIENTED GEOGRAPHIC INFORMATION SYSTEM DATA MODEL FOR TRANSIT TRIP-PLANNING SYSTEMS
• PROTOTYPE CLASSIFICATION TOOL FOR SUPPORTING MAINTENANCE OF TRAFFIC SIGNAL TIMING PLANS
• REAL-TIME TRAFFIC MEASUREMENT FROM SINGLE LOOP INDUCTIVE SIGNATURES
• REDUCTION OF VIDEO LICENSE PLATE DATA
• SIMULATION STUDY OF ESTIMATION OF INDIVIDUAL SPECIFIC VALUES OF TIME BY USING ADAPTIVE STATED-PREFERENCE SURVEY
• SPATIAL BEHAVIORAL DATA: COLLECTION AND USE IN ACTIVITY SCHEDULING MODELS
• TECHNIQUES FOR BUILDING MULTIJURISDICTIONAL GEOGRAPHIC INFORMATION SYSTEM PLATFORMS FOR TRANSPORTATION ANALYSIS
• TEMPORAL DATA CONSTRUCTS FOR MULTIDIMENSIONAL TRANSPORTATION GEOGRAPHIC INFORMATION SYSTEM APPLICATIONS
• TIME-USE METADATA
• TRANSIT VEHICLES AS TRAFFIC PROBE SENSORS
• TRAVEL-TIME ESTIMATES OBTAINED FROM INTELLIGENT TRANSPORTATION SYSTEMS AND INSTRUMENTED TEST VEHICLES: STATISTICAL COMPARISON
• USE OF INTERNET-BASED HOUSEHOLD TRAVEL DIARY SURVEY INSTRUMENT
• USE OF VESSEL FREIGHT DATA TO FORECAST HEAVY TRUCK MOVEMENTS AT SEAPORTS
• XML-BASED TRANSIT TIMETABLE SYSTEM