AN APPLICATION OF MARGINAL UTILITY TO TRAVEL MODE CHOICE

THE INCREASED INTEREST IN PLANNING FOR TRANSIT AS A PORTION OF THE SOLUTION TO URBAN TRANSPORTATION PROBLEMS HAS GENERATED CONCERN FOR THE EFFECTIVENESS OF TRADITIONAL MODAL-CHOICE PREDICTION PROCEDURES. THE CONCERN IS CENTERED ON THE ABILITY OF MODELS CALIBRATED ON DATA REFLECTING BASE-YEAR TRANSPORTATION SERVICE TO PREDICT THE RESULTS OF MARKED CHANGES IN SERVICE. A MODEL THAT IS BASICALLY MORE BEHAVIORISTIC IN NATURE RATHER THAN SIMULATIVE CONCEIVABLY COULD BE AN APPROACH TO A SOLUTION OF THE PROBLEM. A MODAL-CHOICE RELATIONSHIP WAS DEVELOPED THAT UTILIZED AS ITS INDEPENDENT DECISION VARIABLE A COMPOSITE OF SEVERAL, MORE TRADITIONAL FACTORS. IT HAS BEEN THEORIZED THAT COMPONENTS OF THIS VARIABLE REPRESENT THE DISUTILITIES OF TRAVEL BY COMPETING MODES AS PERCEIVED BY THE TRAVELER. THE DIFFERENCES IN DISUTILITY REPRESENT THE MARGINAL DISUTILITY OF A GIVEN MODE. MARGINAL DISUTILITY WAS THE DECISION VARIABLE FOR TRAVELER CHOICE BETWEEN AUTO AND TRANSIT. THE FINAL DECISION VARIABLE COMBINED OUT-OF- POCKET COST OF TRANSIT AND HIGHWAY TRAVEL, FAMILY INCOME, AND PARKING COST, AS WELL AS TRAVEL TIME FOR THE TRIP. MODAL CHOICE WAS EXAMINED FOR 1958 DATA FROM ST. PAUL AND MINNEAPOLIS, USING MARGINAL DISUTILITY AS THE INDEPENDENT VARIABLE. THE RESULTS TRADITIONAL CURVE-FITTING CALIBRATION PROCEDURES. THE DISTRIBUTION OF THE RESULTS APPEARED TO APPROXIMATE QUITE CLOSELY THE NORMAL. THIS SEEMS TO INDICATE THEAT THE VARIABLE USED MAY WELL APPROACH THE ACTUAL, THOUGH UNPERCEIVED, VARIABLE ON WHICH MODAL CHOICES ARE BASED. THE TECHNIQUE HAS THE BENEFITS OF CONCEIVABLE ALLEVIATING THE NEED FOR CALIBRATION AND OFFERING A MORE BASIC, BEHAVIORISTIC FORMULATION THAT MAY TRANSCEND CONSTRAINTS OF TRANSIT SERVICE LEVELS. /AUTHOR/