Taxi Demand Modeling to ensure
appropriate taxi supply
James M Cooper, Transport Research Institute,
Edinburgh Napier University
Wither Taxicab?
• Recognizable and understood mode.
• Single, dual and multiple licensing types.
• Supply impacted by licensed restricted and
free entry markets in similar measure
• Demand analysis models and their application
What are taxi controls?
• Quality, Quantity and Economic Regulation
• Deregulatory Movement
• Taxi Reform
• A central government view
Unpacking the Taxi Model
Analysis by area of regulation
Aggregation, temporal and spatial difference
Legislated Tick Boxes?
So what does the model do, really?
• Applied in the UK to restricted markets
• Seeks to identify where such restriction is
• Demonstrates an index of the level of harm
• By extension, identifies the increase in
licenses required to mitigate the level of harm
• BUT: based on observed delay in one primary
How does this work?
Definition of an Index of SUD (ISUD)
ISUD= APD x ED x Pl x HP
APD Average passenger delay across all time periods
ED Excess Demand, during the Monday to Friday daytime
PI The proportion of taxi users travelling in hours where the
overall average delay at the stance was greater than or
equal to 1 minute
HP Adjustment factor where peaking is present (1 if no
peaking; 0.5 with peaked demand)
Comparative Results
Best Practice
• Department for Transport 2006
• Scottish Government 2007
How has best practice helped?
• YES!
How has best practice helped?
• YES!
• Expanded beyond rank observation
• Introduced “temporal” assessment based on
peaks in demand
• Suggested (but not imposed) seasonality
Has best practice covered all bases?
• NO!
Has best practice covered all bases?
Impact of a licensing based solution
One solution need not fit all
Perverse and negative effects
Non-licensing solutions
Some Driver Perceptions
Night Time Reservations
Achieving time savings
Passenger Delay
Non Licensing Solutions
Other Issues at play
Traffic Signal Delay
Translated in to time saving
Time saving in arrivals at stance is calculated on the
basis of:
TSAS = (CAD x EOT) / (EOT + IGP)
TSAS = Time Saving at Stance
CAD = Current arrival delay, departing from Hope
Street to arrival at Gordon Street
EGT =Effective Green Time
IGP = Increase applied to Green Phase
Impact of time saving
Passenger Delay, at Gordon Street
A quick reminder of principle
• Duties
• Responsibilities
• Impacts
• Utopia gained?
Final Critique
• Does the use of “new” demand models
provide the most appropriate method of
determining market control?
• Why are we ignoring infrastructure, price
impact or quality controls?
So what next?
• Optimality
• Licensinse and infrastructre are both
• Modeled approach not the antithesis of the
free market, but its facilitator
Optimal Information as the guardian of
optimal services
• Restricted markets must not be closed shops
• Deresricted markets must not leave
everything to the market
• Supply issues remain in derestricted market
where infrastructure not appropriate or
• Actual form of regulation does not replace the
need to uderstand, test and respond to the
James Cooper
TRI Taxi Studies Group
[email protected]

Taxi Demand Modeling to ensure appropriate taxi supply