Distributing weekly GRP level to equal allocations, largest audience, largest inventory, proportional to audience, or proportional to inventory. 

Articulated bus (also see slinky bus)

A 60-foot three-axle bus. These buses have an “accordion” section in the middle that allows the bus to bend and flex (articulate). The articulated bus has more passenger capacity than standard 40-foot buses.

Audience Share

The average weekly impressions’ percentage of the plan’s total average weekly impressions

Average Frequency

The average number of times each individual sees the ad

Average speed

The total miles of revenue service divided by the total hours of revenue service. Average speed includes time traveling and time waiting for passengers plus any other delays. Operating without vehicle traffic, heavy rail generally has the fastest average speed. Light rail usually operates in some vehicle traffic. Urban buses are the slowest. Bus Rapid Transit systems are faster.

Average Weekly Impressions

The number of impressions over the course of any given week during the year

Base service

The number of buses that remain in service on a line for the entire day. This does not include buses that only operate during school and commute hour service. Base service is determined by the frequency of buses that must run from the beginning to the end of a line to adequately service riders during off-peak periods (mid-day and evenings).

BRT (Bus Rapid Transit)

A new concept that seeks to achieve a high quality transit service like light rail but at a lower cost using buses. BRT vehicles are generally low-floor, high capacity, low-emission buses, with exclusive rights-of-way, rapid fare collection, and infrastructure development.

Bus class

A vehicle type of bus: high floor, low floor, over the road coach, vans, or an articulated bus. Bus class can also refer to size: 30-foot, 35-foot, 40-foot, 45-foot, and 60-foot. Sometimes the two terms are used together, for example, “30-foot low floor.” Vans are used for ADA (Americans With Disability Act) riders and riders who live in less accessible areas of the city, such as the hills. High capacity buses (articulated and 40-foot low floors) are assigned to run on heavily populated lines.

Bus panel

Advertising panels attached to the exterior or interior of a public bus

Bus shelter

A shelter for riders to wait for the bus

Car Cards

Advertising displays of various sizes posted in buses, subways and commuter trains


Cost Per Thousand impressions

Effective Reach

The percentage of the specified market population reached X number of times


The number of buses, stations, or rail cars that contain advertising being examined.

Environment Count

The quantity of buses or stations.    


The media type


The quantity of service on a route, usually described in terms of the number of buses per hour or the elapsed time between consecutive buses. The latter measure is also called the headway. The term high frequency denotes many buses per hour, or small headways.

Fully Wrapped Bus

Specially commissioned transit display in which the entire bus vehicle is covered with the advertising design, including windows, through which passengers have visibility due to special vinyl material.


A garage and yard facility where buses are stored, maintained, and dispatched into service.


Refers to a manufacturer of transit buses. The Gillig Corporation is located in Hayward, California.

Grid network

A type of route structure. In a typical grid network, high-frequency routes operate along the length of east-west and north-south corridors, intersecting each other to form a grid pattern. This allows a passenger to travel between two points with one transfer. Ideally, routes are spaced ½ miles apart so that riders can easily walk and transfer to any line.

Headlight Displays

Headlight displays are exterior units which appear on the front of a bus, usually under the windshield. 

Heavy Rail

An electric railway system with the capacity to handle a heavy volume of traffic    

HOV (High Occupancy Vehicle)

High occupancy vehicle lanes (carpool lanes), which are lanes reserved for people who share a ride in carpools, vanpools, and/or buses, or who drive a motorcycle. These lanes are marked with a diamond symbol and HOV signs.


The percentage of impressions coming from within the designated market


The percentage of impressions coming from within the designated market

In-Station Media

The basic one-sheet, two-sheet and three-sheet posters are located on subway and train platforms as well as in the track areas of rail terminals.  Urban panels are posters located subway entrances.  All are printed and dry mounted in frames.  Dioramas and mini-spectaculars are giant transparencies, backlit to enhance visibility.   

Interior Bus Cards

Interior bus cards are positioned in frames above passenger seats.  Some markets offer backlit panels.  In some systems, a single advertiser can purchase all of the cards on vehicle to create a “brand bus,” often used in conjunction with a fully-wrapped exterior. 

Interior Car Cards

Interior subway car cards are positioned in frames above passenger seats.  Some markets offer backlit panels.  Rail cards are on bulkhead walls of most commuter coaches, near doors. 


The quantity of available panels.    

Inventory Name

The transit system and available format

Inventory Share

The inventory’s percentage of the plan’s total inventory

King Size Bus Panel

Long standardized advertising panels affixed to the exterior of public buses.  The king-size bus poster is an exterior display which may appear on either side of the bus. 

Kong-Size Bus Posters

The Kong-size bus poster is an exterior display usually appearing on the street side of a bus.   

Layover time

The time built into a schedule between arrival and departure for bus drivers to rest; minimum times are set by union contract. Layovers normally occur at each end of a route to allow for a driver’s break and schedule recovery, but they may be scheduled at other points to allow for timed transfer connections.

Light Rail

A mode of transit service (also called streetcar, tramway, trolley or LRT) operating passenger rail cars singly (or in short, usually two-car or three-car, trains) on fixed rails in right-of-way that is often separated from other traffic for part or much of the way. Light rail vehicles are typically driven electrically with power being drawn from an overhead electric line via a trolley or a pantograph; driven by an operator on board the vehicle; and may have either high platform loading or low level boarding using steps.

Limited stop service

A route segment where designated buses stop only at transfer points or major activity centers, usually about every ½ mile. Limited stop service is usually provided on major trunk lines, in addition to local service that makes all stops.

Linked/Unlinked trip

A trip where a rider may transfer between types of vehicles, or multiple stops, such as stopping at a daycare center or store along a commute trip. An unlinked trip is a passenger trip taken on a single vehicle, such as a single bus  or subway ride.


A portion of a bus line where the driver operates a segment in one direction only. Passengers may only board on one side of the loop. Loops are sometimes required due to lack of pavement accessibility, or when no off street turn-around is available.

LOS (Level of Service)

A measure of congestion that compares actual or projected traffic volume with the maximum capacity of the intersection or road in question. LOS is rated from A (free-flowing traffic) to F (gridlock).

Mass Transit Transportation

Public conveyances such as buses, trains, subways and other rapid transit commuter systems. 

MCI (Motor Coach Industries)

A manufacturer of the 45-foot commuter buses with a seating capacity of 57 and a standing capacity of 13. The headquarters of MCI is in Schaumburg, Illinois

Mobile Billboard

A truck that is equipped with one or more standard poster panels that are intended for viewing while the vehicle is parked at specified locations or while driving along a designated route. 


The availability of multiple transportation options, especially within a system or corridor. A multimodal approach to transportation planning focuses on the most efficient way of getting people or goods from place to place by means other than privately owned vehicles; by bus, trolley, light rail, streetcar, cable car, and / or ferry systems.

NABI (North American Bus Industries)

A manufacturer of transit buses. Corporate NABI headquarters is located in Anniston, Alabama.

New Flyer

A manufacturer of transit buses. Corporate New Flyer headquarters is in Winnipeg, Manitoba, Canada, and the assembly plant is located in Crookston, Minnesota. 


A term used by schedulers to define the actual time a bus arrives at a designated stop or time point.

Owl Service

Buses that run after midnight that provide round-the-clock service


Bundle of panels sold as unit

Panels Per Environment

The average number of panels on one bus, station, etc. 


Scheduled service for people who cannot use regular fixed-route bus service.

Peak service

Weekday a.m. and p.m. service during commute hours to carry a maximum number of passengers. Commute or peak hours are defined as time between 6 and 9 a.m. in the morning, and between 4 and 7 p.m. at night.

Queen-Size Bus Poster

The queen-size bus poster is an exterior display which usually appears on the curb side of the bus.

Rail Advertising

Station or terminal advertising that is positioned in close proximity to train tracks. 

Rear Bus Panel

A standard panel affixed to the back exterior of public buses. 

Round trip (Also known as a cycle)

One inbound, plus one outbound trip (unless a loop route), equals one round trip or cycle.


The targeted garage, station, or line.


The media category

Slinky bus

A nickname used by many passengers for the articulated bus.


The percentage of impressions coming from outside the designated market

Spread Time

The total time from the start of a driver assignment to its end, whether a bus is in service or not.

Station Advertising

Advertising panels located in subway or commuter rail stations or on transit platforms.  Sizes vary. 

Station Posters

Framed, mounted on walls of subway platforms and walkways. 

Subway Advertising

Advertising panels located in subway or commuter rail stations or on transit platforms.  Sizes vary

Subway Brand Trains

Inter Car card program provides “total” uninterrupted media environment for one advertisier by using half or all card locations in car. 

Taillight Displays

Taillight displays are exterior units appearing at the rear of the bus, usually under the windows. 

Target GRP

The percentage of impressions coming from within the designated market

Target Impressions

The total Impressions for the specified target

Target Reach

The percentage of the specified market population reached

Time point

A location on a bus route assigned a fixed scheduled time that is part of a larger line schedule.

Timed transfer

A system of scheduling transit so that connecting routes come together at the same time. This allows passengers convenient no-wait transfers between bus lines. Timed transfers are frequently used with owl (late-night) service.

Transfer point

A point where bus lines intersect and passengers can transfer to another line.

Transit Advertising

Advertising displays affixed to moving vehicles or in the common areas of transit stations, terminals and airports.  Transit displays include, but are not limited to: interior and exterior bus panels, subway and rail panels, ferry stations and terminals, taxi panels, and truckside panels.  


An electric rail transport vehicle also known as a trolley or streetcar. Some modern light rail systems are also referred to as trolleys.  May also refer to trolley bus

Truckside Advertising

Mobile billboard (truck-mounted) displays are poster panels affixed to aerodynamically-designed vehicles (generally 30-sheet size).  Specially outfitted mobile units with electronic, 3-D, or video screen displays are available. 

Van Hool Bus

A Euro-style bus manufactured in Antwerp, Belgium.


The company selling the advertisement space

VMT (Vehicle Miles Traveled)

Refers to the numbers of cars that are on the road at the same time in the same area. The greater the number, the worse the congestion will be. Reducing the growth of VMT can help ease traffic congestion and improve air quality.

Weekly Target GRP

The average weekly Gross Rating Points for specified target


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