Shared Mobility Parameters

Parameter related to modeling and simulation a shared fleet are described here. Primarily, the shared mobility parameters are contained within the file specified by tnc_fleet_model_file in the scenario file. The typical filename for these parameters is TNCFleetModel.json. You may also come across instances of SAVFleetModel.json or ChicagoTNCFleetModel.json.

The remaining page describes parameters at the TNC Operator level first and strategy-specific parameters follow.

TNC Operator Chooser Model Parameters

These are the decision parameters on choosing operators as well as choice model parameters that control how operators are chosen from those available. The parameters are contained within two files that are specified in the scenario.json via parameter tnc_fleet_model_file and tnc_operator_chooser_model_file.

These parameters are read in in the TNC_Operator_Chooser_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
ASCs	ASC_DRS_YES	Alternative specific constant with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO	Alternative specific constant without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_SIX_SEATER	Alternative specific constant for six-seater vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_SIX_SEATER	Alternative specific constant for six-seater vehicle without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_FOUR_SEATER	Alternative specific constant for four-seater vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_FOUR_SEATER	Alternative specific constant four-seater vehicle without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_SIX_SEATER_STANDARD	Alternative specific constant for six-seater economy vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_SIX_SEATER_LUX	Alternative specific constant for six-seater luxury vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_SIX_SEATER_STANDARD	Alternative specific constant for six-seater economy vehicle without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_SIX_SEATER_LUX	Alternative specific constant for six-seater luxury vehicle without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_FOUR_SEATER_STANDARD	Alternative specific constant for four-seater economy vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_YES_FOUR_SEATER_LUX	Alternative specific constant for four-seater luxury vehicle with dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_FOUR_SEATER_STANDARD	Alternative specific constant for four-seater economy vehicle without dynamic ride sharing (pooling)	nan	float
	ASC_DRS_NO_FOUR_SEATER_LUX	Alternative specific constant for four-seater vehicle without dynamic ride sharing (pooling)	nan	float
Cost Parameter	B_COST_DRS_YES_SIX_SEATER_STANDARD	Cost coefficient for six-seater economy vehicle with dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_YES_SIX_SEATER_LUX	Cost coefficient for six-seater luxury vehicle with dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_NO_SIX_SEATER_STANDARD	Cost coefficient for six-seater economy vehicle without dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_NO_SIX_SEATER_LUX	Cost coefficient for six-seater luxury vehicle without dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_YES_FOUR_SEATER_STANDARD	Cost coefficient for four-seater economy vehicle with dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_YES_FOUR_SEATER_LUX	Cost coefficient for four-seater luxury vehicle with dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_NO_FOUR_SEATER_STANDARD	Cost coefficient for six-seater economy vehicle without dynamic ride sharing (pooling)	nan	float
	B_COST_DRS_NO_FOUR_SEATER_LUX	Cost coefficient for six-seater luxury vehicle without dynamic ride sharing (pooling)	nan	float
Nesting Coefficient	LAMBDA_DRS_YES	Nesting parameter for pooling nest	nan	float
	LAMBDA_DRS_NO	Nesting parameter for non-pooling nest	nan	float
	LAMBDA_DRS_YES_SIX_SEATER	Nesting parameter for pooling nest with six-seater vehicle	nan	float
	LAMBDA_DRS_NO_SIX_SEATER	Nesting parameter for non-pooling nest with six-seater vehicle	nan	float
	LAMBDA_DRS_YES_FOUR_SEATER	Nesting parameter for pooling nest with four-seater vehicle	nan	float
	LAMBDA_DRS_NO_FOUR_SEATER	Nesting parameter for non-pooling nest with four-seater vehicle	nan	float
Service Choice	use_service_choice	Boolean to use service choice in the model or not. Triggers the use of parameters in the nested logit for service and seating choice.	nan	boolean
Time Parameter	B_IVTT_DRS_YES_SIX_SEATER_STANDARD	In-vehicle travel time coefficient for six-seater economy with dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_YES_SIX_SEATER_LUX	In-vehicle travel time coefficient for six-seater luxury vehicle with dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_NO_SIX_SEATER_STANDARD	In-vehicle travel time coefficient for six-seater economy vehicle without dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_NO_SIX_SEATER_LUX	In-vehicle travel time coefficient for six-seater luxury without dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_YES_FOUR_SEATER_STANDARD	In-vehicle travel time coefficient for six-seater vehicle with dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_YES_FOUR_SEATER_LUX	In-vehicle travel time coefficient for six-seater vehicle with dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_NO_FOUR_SEATER_STANDARD	In-vehicle travel time coefficient for six-seater vehicle without dynamic ride sharing (pooling)	nan	float
	B_IVTT_DRS_NO_FOUR_SEATER_LUX	In-vehicle travel time coefficient for six-seater vehicle without dynamic ride sharing (pooling)	nan	float

TNC Fleet Model Parameters

These are the TNC fleet model parameters that control the high-level fleet characteristics. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Operator_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Electric TNC Vehicle	SAME_EV_RANGE_FLAG	Flag to set the EV range uniformly across the fleet for each operator	nan	boolean
	EV_INITIAL_SoC_RANGE_FLAG	Flag to set the EV battery mean and std dev, if not all EVs will start with 100% battery	nan	boolean
	SET_OF_EV_RANGES	Discrete set of EV range for assigning to vehicles in mi. Talk to Murthy before using this feature - may not work.	nan	IntArray
	RANGE_DISTRIBUTION	Distribution of the different ranges in SET_OF_EV_RANGES for assigning to vehicles. Talk to Murthy before using this feature - may not work.	nan	FloatArray
	EV_RANGE_MILES	If SAME_EV_RANGE_FLAG is True, specify the range of the EV in miles.	nan	float
	EV_INIT_SoC_MEAN	If EV_INITIAL_SoC_RANGE_FLAG is true, the set the mean of the distribution in whole percent (for example, use 85 to denote 85%)	nan	float
	EV_INIT_SoC_SD	If EV_INITIAL_SoC_RANGE_FLAG is true, the set the standard deivation of the distribution in whole percent (for example, for 1% use 1)	nan	float
	Euclidian_Factor	Euclidean factor used to inflate distance used in approximate range utilization calculations before assigning requests to vehicles	nan	float
Fleet Characteristics	TNC_FLEET_SIZE	Fleet size of shared vehicles to simulate in the region. This will be scaled by the traffic_scale_factor within the simulation. Minimum value by default is 1.	nan	integer
	TNC_MAX_WAIT_TIME	Maximum wait time in minutes used in searching for nearby vehicle candidates for matching. This time includes assignment and pickup time.	nan	float
	TNC_WAIT_ASSIGNMENT_TIME	Maximum time to allow a request to wait for a vehicle match, after which the request will be failed.	nan	float
	TNC_PREBOOKING_ASSIGNMENT_TIME	Time before a reservation to start looking for an assignment	nan	float
	TNC_MAX_SEATED_CAPACITY	Default value for number of seats in all vehicles within the fleet. Will soon rely on vehicle characteristics for number of seats.	nan	float
	delivery_type	String that specifies what types of requests are catered to by each operator. Possible options currently are "person", "meals_and_grocery", "relocator", and "mixed".	nan	string
Human Driver Operation	human_driver_ratio	Decimal fraction of vehicles in the fleet that are operated by human drivers	nan	float
	human_request_cancellation_prob	Decimal probability of drivers cancelling a request	nan	float
	human_driver_types_dist	Distribution of human drivers who may stay in place while not serving a trip, repoisition to zone expected to have high demand, reposition to zone expected to have high surge factor.	nan	FloatArray
	driver_rating_min	Minimum value of driver rating when using a uniform distribution	nan	float
	driver_rating_max	Maximum value of driver rating when using a uniform distribution	nan	float
Operational Constraints	geofence_flag	Flag to denote if the shared mobility service is limited to operate within a geofence	nan	boolean
	geofence_zonebased_flag	If geofence_flag is true, flag to specific if the geofence is defined using zone IDs	nan	boolean
	geofence_inclusion_zones	If geofence_zonebased_flag is true, set of zones where operator CAN serve trips	nan	IntArray
	geofence_exclusion_zones	If geofence_zonebased_flag is true, set of zones where operator CANNOT serve trips	nan	IntArray
	geofence_areatype_limit	If geofence_zonebased_flag is false, areatype limit less than within which the operator can serve trip	nan	float
TNC Demand	force_tnc_over_auto	Flag to force all auto demand to use shared mobility	nan	boolean
	use_fmlm	Flag to set if operator supports pickups and dropoffs at transit stops for first-mile-last-mile trips	nan	boolean
	magic_fmlm	Flag to allow router-only first-mile-last-mile trips without passing trips through to actual shared vehicles in the simulation. This means no wait time or travel delays are experienced.	nan	boolean
	overwrite_input_party_size	Flag to set the distribution of request party size using an input, as opposed to reading it from the Demand database	nan	boolean
	party_size_distribution	if overwrite_input_party_size is true, the distribution of 1,2,3, and 4-person parties can be set for generation	nan	FloatArray
TNC Maintenance	uniform_service_dist	Flag that controls if shared mobility maintenance is randomly distributed throughout the simulation day	nan	boolean
	service_dist	Ability to specific the hourly probability distribution of when shared vehicles need to sent for maintenance/cleaning	nan	FloatArray
TNC Pooling	pooling_discount_for_fare	Percentage of discount offered on total fare when pooling ride is requested	nan	float
TNC Services and Operators	services_offered	Set of services offered by an Operator	nan	StringArray
	dist_services_offered	Distribution of fleets by service type. It should sum to 1.	nan	FloatArray
	market_capture_prob_for_loyalty	Market share of Operators (between 0 and 1)	nan	float
TNC Strategy	strategy_name	User-provided strategy name to define a collection of control-specific strategies to load that the operator will use. The name chosen here should be a section available in the input model file and should contain strategy-specific parameters.	nan	string
	init_vehicle_state_strategy	Strategy name to load to initialize vehicle state for a run. Available options in the theory section on shared mobility.	nan	string
	assignment_strategy	Strategy name to load for assignment or matching. Available options in the theory section on shared mobility.	nan	string
	fare_strategy	Strategy name to load for setting fares after trip completion or to query an estimate before trip. Available options in the theory section on shared mobility.	nan	string
	reposition_strategy	Strategy name to load repositioning control of fleet. Available options in the theory section on shared mobility.	nan	string
	charging_strategy	Strategy name to load charging and discharging behavior. Available options in the theory section on shared mobility.	nan	string
	maintenance_strategy	Strategy name to load for maintenance and cleaning of fleet. Available options in the theory section on shared mobility.	nan	string
	parking_strategy	Strategy name to load to control parking between trips. Available options in the theory section on shared mobility.	nan	string
TNC_Operator	ZONE_BASED_ASSIGNMENT	Should always be true. Storage architecture for finding nearby vehicles.	nan	boolean
	TNC_LOGGING_INTERVAL	Interval in minutes where outputs are logged to DB	nan	float

TNC Default Strategy Model Parameters

These are the strategy parameters that decide how the TNC fleet operates during the simulation. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Default_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Default_Strategy	MAX_EVCS_WAIT_MINUTES	To be moved	nan	nan
	EVCS_MIN_DCFC_PLUGS	To be moved	nan	nan
	EVCS_MAX_DCFC_PLUGS	To be moved	nan	nan
Electric TNC Vehicle	MIN_EV_SoC	Minimum electric vehicle state of charge below which vehicle will stop accepting requests. Required by all strategies that use EVs.	nan	float
	CUTOFF_BATTERY_LEVEL	The maximum battery level to charge the electric shared vehicle up to before charging is cutoff. Required by all strategies that support EV operation.	nan	float
Parking_Strategy	parking_flag	Flag that ensures shared vehicles park at a parking location if set. Required for all parking strategies.	nan	boolean
	rideshare_minimize_park_cost	Flag that, when true, minimizes a parking cost that is a function of distance and money charged, and minimizes distance if false.	nan	boolean
	rideshare_max_park_distance	Maximum parking distance in meters that is allowed.	nan	float
	rideshare_max_park_cost	Maximum dollar charge for parking that is allowed	nan	float
	rideshare_avg_park_time	Average parking time in minutes assumed for cost calculation when finding nearest parking	nan	float
Pooling	DRS_FLAG	Flag that controls if dynamic ride-sharing or pooling is active or not. Required for all matching strategies.	nan	boolean
	DRS_MAX_ALLOWABLE_DELAY_SECONDS	Theoretic maximum allowable delay that any request can experience when pooled. Required for all matching strategies.	nan	float
	DRS_MAX_PERC_DELAY	Theoretical maximum percentage delay compared to door-to-door travel time when pooled. Required for all matching strategies.	nan	float
	directionality_threshold_degrees	Deviation in degrees from line connecting current trip's O to D relative to line connecting O to new request's pickup.	nan	float
Repositioning	repositioning_flag	Flag that controls if fleet repositions or not. Required for all repositioning strategies.	nan	boolean
	demand_window_size	Fraction of an hour used to aggregate past demand for use as a predictor of future demand	nan	float
	time_tradeoff	Travel time tradeoff in seconds above which repositioning is executed	nan	float
	alpha	Factor of past demand used for prediction to ensure some smoothness in how many vehicles to reposition	nan	float
TNC Maintenance	SERVICE_FLAG	Flag that controls whether or not the shared fleet vehicles are periodically subject to maintenance and cleaning	nan	boolean
	SERVICE_CONVENIENCE_FLAG	Flag that allows scheduling a maintenance trip if the vehicle's current destination is relatively close to a maintenance station	nan	boolean
	SERVICE_DISTANCE	If SERVICE_CONVENIENCE_FLAG is true, then this is the distance in miles from current destination to a nearby maintenace depot that is allowed	nan	float
	service_time	Time in minutes taken to perform service/maintenance	nan	float
	clean_service_time	Time in minutes taken to perform vehicle cleaning	nan	float
	max_service_trips_per_day	Maximum number of service/maintenance/cleaning trips that a shared vehicle can be subject to in a simulation day	nan	float
	max_tours_before_cleaning	Maximum tour chains (a series of pickup and dropoffs in the case of pooling) before the vehicle needs to be cleaned	nan	float

Georgia Tech’s ODMTS Strategy Model Parameters

Assignment strategy parameters used to initialize and operate Georgia Tech’s ODMTS pooling strategy. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Riley2018_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type

Joint Electric Vehicle Charging and Repositioning Strategy Model Parameters

Assignment and repositioning strategy parameters used to initialize and operate UT’s joint EVCR strategy. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Joint_EVCR_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Electric TNC Vehicle	EV_LEVEL_UTILITY_INCREASE	The weight parameter (determined by modeler discretion) to increase charging by increasing the objective value (alpha in paper)	nan	nan
	EV_SUPPLY_LEVEL_SOC	The minimum state of charge (SOC) for a vehicle to count as eligible for repositioning in a supply sense (say 40.0 for 40%)	nan	nan
	EV_REPOSITIONING_MIN_SoC	Minimum level for a vehicle to be eligible for repositioning when reviewing idle vehicles to reposition (say 40 for 40%).	nan	nan
	CUTOFF_BATTERY_LEVEL	State of charge (SoC) when battery will stop charging (say 95.0 for 95%)	nan	nan
	EV_QUEUE_FACTOR	Sets the number of available parking spots at the charging stations where vehicles can queue while waiting to charge (multiplied by # of plugs at the zonal level) (say 0.30).	nan	nan
Joint_Charging_Repositioning_Strategy	time_tradeoff	Weight parameter (determined by modeler discretion) to penalize unmet demand, represented in the slack variable. It is also used to exclude faraway zones (by estimated travel time) for each eligible repositioning vehicle.	nan	float
	alpha	Factor of past demand used for prediction to ensure some smoothness in how many vehicles to reposition	nan	float
Required Strategy Parameters	repositioning_flag	Flag that controls if fleet repositions or not. Required for all repositioning strategies.	nan	boolean

Stable Matching Strategy Parameters

These are the strategy parameters specific to using the stable matching strategy that balances rider and driver preferences. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Stable_Matching_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Algorithm Weights	ev_preference_factor	Preference weight for choosing an electric vehicle	nan	float
	driver_rating_weight	Preference weight for driver rating of vehicle that is a viable candidate	nan	float
Pooling	DRS_FLAG	Flag that controls if dynamic ride-sharing or pooling is active or not. Required for all matching strategies.	nan	boolean
	DRS_MAX_ALLOWABLE_DELAY_SECONDS	Theoretic maximum allowable delay that any request can experience when pooled. Required for all matching strategies.	nan	float
	DRS_MAX_PERC_DELAY	Theoretical maximum percentage delay compared to door-to-door travel time when pooled. Required for all matching strategies.	nan	float
Preferences	matching_request_preference	Boolean to consider request preference matching in algorithm	nan	boolean
	matching_vehicle_preference	Boolean to consider vehicle preference matching in algorithm	nan	boolean

Dynamic Fare Strategy Parameters

These are the strategy parameters specific to using the dynamic fare setting policies. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_Dynamic_Fare_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Fare Controls	dynamic_fare_flag	Boolean to set whether fares vary dynamically throughout the simulation or a fixed per-mi, per minute, and base fare will be applied to request	nan	boolean
	tod_fare_flag	Boolean for specific type of dynamic fare strategy that only is applied for particular times of day	nan	boolean
	TOD_surge_factor	Factor applied to fares in the designated times of day to surge fares	nan	float
	zone_surge_multiplier_flag	Maximum factor applied to fares in particular zones that meet demand and supply criteria to surge fares	nan	float
	surge_calculation_interval	Simulation time in seconds to update the surges used for each zone	nan	float
Time Periods	rideshare_am_peak_period_start	Simulation time in hour of day to denote the start of AM peak period for ridehailing/ridesharing trips	nan	float
	rideshare_am_peak_period_end	Simulation time in hour of day to denote the end of AM peak period for ridehailing/ridesharing trips	nan	float
	rideshare_pm_peak_period_start	Simulation time in hour of day to denote the start of PM peak period for ridehailing/ridesharing trips	nan	float
	rideshare_pm_peak_period_end	Simulation time in hour of day to denote the end of PM peak period for ridehailing/ridesharing trips	nan	float

Alonso-Mora et al.’s Ride-Sharing Strategy Parameters

These are the parameters specific to running the AlonsoMora strategy for assignment. The parameters are contained within the file that is specified in the scenario.json via parameter tnc_fleet_model_file.

These parameters are read in in the TNC_DRS_AlonsoMora_Strategy_Methods.h header file.

Category	Parameter Name	Description	Default	Data Type
Optimization	batched_interval_seconds	Interval in seconds to batch requests before applying matching optimization	nan	float
	n_vehicles_per_request	Number of vehicles considered as a candidate for each request.	nan	integar
Pooling	DRS_FLAG	Flag that controls if dynamic ride-sharing or pooling is active or not. Required for all matching strategies.	nan	boolean
	DRS_MAX_ALLOWABLE_DELAY_SECONDS	Theoretic maximum allowable delay that any request can experience when pooled. Required for all matching strategies.	nan	float
	DRS_MAX_PERC_DELAY	Theoretical maximum percentage delay compared to door-to-door travel time when pooled. Required for all matching strategies.	nan	float
Routing	TT_cutoff_for_routing_vs_skim_seconds	If strategy uses router to get travel time (instead of skims), the cutoff value below which the router is used.	nan	float