By M. Janson and D. Levinson, August 7, 2013
The Minnesota Department of Transportation (MnDOT) has added MnPASS High
Occupancy Toll (HOT) lanes on two freeway corridors. While not the
first HOT lanes in the country, the MnPASS lanes are the first
implementation of road pricing in Minnesota and possess a dynamic
pricing schedule. Tolls charged to single occupancy vehicles (SOVs) are
adjusted every three minutes according to HOT lane vehicle density.
Given the infancy of systems like MnPASS, questions remain about
drivers’ responses to toll prices. Three field experiments were
conducted on the corridors during which prices were changed. Data from
the field experiments as well as two years of toll and traffic data were
analyzed to measure driver responses to pricing changes. Driver
elasticity to price was positive with magnitudes less than 1.0. This
positive relationship between price and demand is in contrast with the
previously held belief that raising the price would discourage demand.
We hypothesize this is because drivers use price as a signal of time
savings. In addition, drivers consistently paid between approximately
$60-120 per hour of travel time savings, much higher than the average
value of time. Reasoning for these results is discussed as well as the
implications these results have on the pricing of HOT lanes.