AN EMPIRICAL MODEL FOR MULTILANE ROAD TRAFFIC

SOME OF THE METHODS OF DESCRIPTION OF SINGLE-LANE TRAFFIC INCLUDING THE USE OF HEADWAY AND COUNTING DISTRIBUTIONS ARE DESCRIBED. ANOTHER METHOD OF DESCRIBING POINT PROCESSES IS BY MEANS OF PRODUCT DENSITIES. THESE ARE ESSENTIALLY JOINT PROBABILITIES OF TWO OR MORE VEHICLES PASSING A POINT AT DIFFERENT SPECIFIED TIMES. PRODUCT DENSITIES HABE BEEN USED IN MANY FIELDS INCLUDING PARTICLE PHYSICS, ECOLOGY, AND ROAD TRAFFIC. THE IDEA OF USING PRODUCT DENSITIES IS SIMPLE AND ATTRACTIVE, BUT THEY DO HAVE TWO MAJOR DISADVANTAGES: (1) EXCEPT IN SIMPLE CASES HEADWAY DISTRIBUTIONS ARE VERY DIFFICULT TO DERIVE FROM PRODUCT DENSITIES, AND (2) PRODUCT DENSITY ESTIMATES FOR DIFFERENT TIME LAGS ARE CORRELATED, SO THAT TESTS OF HYPOTHESES ARE NOT EASY TO PERFORM. AN ALTERNATIVE TO PRODUCT DENSITIES IS PROPOSED. FOR WANT OF A BETTER NAME THESE ARE CALLED TERMINATION RATES. THE TERMINATION RATE AFTER LAG IS THE PROBABILITY OF A VEHICLE PASSING A POINT IN A SMALL INTERVAL OF TIME, DIVIDED BY THE LENGTH OF THE SMALL INTERVAL AND CONDITIONAL UPON THE LAST VEHICLE HAVING PASSED A TIME PREVIOUSLY. THESE ARE VERY SIMILAR TO MORTALITY RATES FOR HUMANS OR SCRAPPAGE RAGES FOR COMMODITIES WITH LIMITED LIFE-TIMES. THE INTERRELATIONS BETWEEN THESE STATISTICS ARE QUOTED BUT NOT DERIVED. VARIOUS SETS OF DATA ARE USED TO ILLUSTRATE THE LESS COMMON STATISTICS. SOME ANALYSIS IS GIVEN OF A SAMPLE OF DATA FROM THE CONGRESS (NOW EISENHOWER) EXPRESSWAY IN CHICAGO. VARIANCE TO MEAN RATIOS ARE USED TO SHOW THAT THERE IS A STRONG CORRELATION BETWEEN LANES EVEN THOUGH THE AUTOCORRELATIONS OF HEADWAYS WITHIN LANES ARE VERY SMALL. BIVARIATE TERMINATION RATES HAVE BEEN ESTIMATED FOR EACH LANE. GIVEN A VEHICLE IN ONE LANE, IT WAS FOUND THAT EXPECTED NUMBER OF VEHICLES IN A NEIGHBORING LANE WITHIN 2 OR 3 SEC WAS ENHANCED BY ABOUT 10-15%. /AUTHOR/

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/1767714
• Supplemental Notes:
  • Vol 4, No 2, PP 164-186, 10 FIG, 4 TAB, 17 REF
• Corporate Authors:

  Operations Research Society of America

  428 East Preston Street
  Baltimore, MD  United States  21202
• Authors:
  • Miller, A J
• Publication Date: 0

Media Info

• Serial:
  • Transportation Science
  • Volume: 5
  • Issue Number: 2
  • Publisher: Institute for Operations Research and the Management Sciences (INFORMS)
  • ISSN: 0041-1655
  • Serial URL: http://transci.journal.informs.org/

Subject/Index Terms

• TRT Terms: Headways; Mathematical models; Multilane highways; Single lane traffic; Statistical analysis; Traffic density; Traffic simulation
• Subject Areas: Data and Information Technology; Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00227274
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 26 1970 12:00AM