ESTIMATING ANNUAL AVERAGE DAILY TRAFFIC FROM SHORT-TERM TRAFFIC COUNTS

THE PURPOSE OF THIS STUDY WAS TO EVALUATE A METHOD ADVOCATED BY THE U. S. BUREAU OF PUBLIC ROADS FOR ESTIMATING ANNUAL AVERAGE DAILY TRAFFIC FROM SHORT-TERM TRAFFIC COUNTS AND TO DETERMINE WHETHER EXISTING PROCEDURES COULD BE IMPROVED WITH REDUCED ANNUAL COST. THIS STUDY PERTAINED TO RURAL ROADS CARRYING 500 OR MORE VEHICLES PER DAY. SOME OF THE FIRST TESTS WERE CONDUCTED FOR THE PURPOSE OF DETERMINING THE MOST SATISFACTORY METHOD OF GROUPING CONTINUOUS COUNTING STATIONS AND THE COMPUTATION OF MEAN MONTHLY ADJUSTMENT FACTORS FOR EACH GROUP. ONE OF THE FIRST CONCLUSIONS WAS THAT CONTINUOUS COUNT STATIONS SHOULD BE GROUPED ON THE BASIS OF AVERAGE MONTHLY ADJUSTMENT FACTORS OF SEVERAL CONSECUTIVE YEARS RATHER THAN ON THE BASIS OF THE FACTORS FOR ANY SINGLE YEAR. IT WAS FURTHER CONCLUDED THAT DIVISION OF THE STATES RURAL ROADWAYS INTO FIVE GROUPS WOULD BE SUFFICIENT STRATIFICATION OF ANNUAL PATTERNS OF TRAFFIC VOLUME VARIATION. TESTS WERE MADE TO DETERMINE THE RELATIVE EFFICIENCY OF SEASONAL CONTROL COUNTS REPEATED A VARIOUS NUMBER OF TIMES PER YEAR PER LOCATION FOR ESTABLISHING GROUP ASSIGNMENTS OF ROADWAY SECTIONS AND ESTIMATING AADT. TESTS WERE MADE PERTAINING TO SEASONAL CONTROL COUNTS REPEATED FOUR, SIX AND TWELVE TIMES A YEAR PER LOCATION. THE STANDARD DEVIATIONS OF THE ERRORS OF ESTIMATED AADT FROM SEASONAL CONTROL COUNTS OF FOUR, SIX AND TWELVE TIMES PER YEAR WERE 3.6, 3.1 AND 1.7 PERCENT, RESPECTIVELY. COMPARISONS OF THE RESULTS OF USING VARIOUS SEASONAL CONTROL COUNTS TO INDICATE GROUP ASSIGNMENT OF ROADWAY SECTIONS SHOWED NO SIGNIFICANT DIFFERENCE. THE MISSOURI STATE HIGHWAY DEPARTMENT IS CONSIDERING THE ADOPTION OF THE BUREAUS METHOD OF ESTIMATING AADT USING A 7-DAY COVERAGE COUNT PROGRAM AND SEASONAL CONTROL COUNTS REPEATED FOUR TIMES A YEAR PER LOCATION. IT IS BELIEVED THAT THE EVENTUAL ANNUAL SAVINGS OF THIS METHOD WOULD BE APPROXIMATELY ONE-HALF THE COST OF THE CURRENT PROGRAM. /AUTHOR/

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures; Tables;
  • Pagination: pp 85-95
  • Monograph Title: Statistical and mathematical aspects of traffic
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00227477
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 15 2004 2:36AM