CALIFORNIA METHOD OF ASSIGNING DIVERTED TRAFFIC TO PROPOSED FREEWAYS

CALIFORNIA HAS DEVELOPED A SET OF CURVES SHOWING PERCENT OF FREEWAY USAGE AS A FUNCTION OF BOTH TIME AND DISTANCE DIFFERENTIALS. THE PRIMARY FEATURES OF THIS CHART ARE THAT IT SHOWS: (1) AS LONG AS SOME TIME IS SAVED, THERE WILL BE SOME USERS OF THE FREEWAY ROUTE NO MATTER HOW FAR OUT OF DIRECTION THEY MUST GO, (2) AS LONG AS SOME DISTANCE IS LOST, THERE WILL BE SOME 'NON-USERS', NO MATTER HOW MUCH TIME IS SAVED, (3) IN BETWEEN THERE IS A GRAY AREA WHERE PEOPLE DO NOT KNOW HOW MUCH TIME OR DISTANCE IS SAVED OR LOST, OR WHETHER IT IS SAVED OR LOST. THE AREA BETWEEN THE LIMITING BOUNDARIES DESCRIBED IN (1) AND (2) WAS FILLED BY A SYSTEMATIC SET OF USAGE CURVES AND THE COEFFICIENTS WERE DETERMINED BY OBSERVATION OF TWO EXISTING FREEWAYS, I.E., BY INTERVIEWING THE USERS AND COMPARING WITH TOTAL INTERZONE TRANSFERS. THE CHART WAS THEN TESTED AGAINST THE SHIRLEY HIGHWAY DATA REPORTED BY D. L. TRUEBLOOD IN HRB BULLETIN 61, AND WAS FOUND TO FIT RELATIVELY WELL. AT LEAST THE TIME-RATIO CURVES FIT THE CALIFORNIA DATA. IN CALIFORNIA, WHENEVER A ROUTE STUDY INVOLVES NEW LOCATION OR MORE THAN ONE ALTERNATE SOLUTION, A COMPLETE ECONOMIC ANALYSIS IS MADE, SHOWING USER COSTS FOR THE COMMON SET OF TRIPS WHETHER MADE VIA ANY ONE OF THE PROPOSED ALTERNATES OR VIA REMAINING ROADS. THIS WORK IS DONE IN CONJUNCTION WITH THE ASSIGNMENT, BY PUNCH CARD MACHINES. THE MANUAL CODING NECESSARY CONSISTS OF CODING THE DISTANCE VIA EXISTING NETWORKS FOR EACH INTERZONE TRANSFER, AND THE DISTANCE BETWEEN ACCESS POINTS ALONG THE LINE OF EACH FREEWAY ALTERNATE. THE ASSIGNMENT CURVES ARE EXPRESSED AS A FORMULA FOR THE PURPOSE OF MACHINE MANIPULATION. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrbbulletin/130/130-001.pdf
• Supplemental Notes:
  • No 130, pp 1-26, 14 FIG, 7 TAB, 3 REF Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Moskowitz, Karl
• Publication Date: 1956

Media Info

• Media Type: Digital/other
• Pagination: 26p
• Monograph Title: Traffic assignment by mechanical methods
• Serial:
  • Highway Research Board Bulletin
  • Issue Number: 130
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Benefits; Coding systems; Distance; Economic analysis; Freeways; Information processing; Punched cards; Traffic assignment; Traffic diversion; Travel; Travel time; Travelers
• Old TRIS Terms: Coding; Freeway benefits; Freeway usage
• Subject Areas: Economics; Highways; Operations and Traffic Management; Society;

Filing Info

• Accession Number: 00225426
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Apr 28 1994 12:00AM