Historical Development of the North Jersey Regional Transportation Model (NJRTM)
Northern New Jersey’s first regional travel demand model (a conventional four-step model) was developed in the late 1980s by the New Jersey Department of Transportation and NJTPA. This model was calibrated using data from a home interview survey conducted in 1986, along with 1980 census data. The model was called the North Jersey Regional Transportation Model (NJRTM) and ran on TRANPLAN software. Modifications and enhancements throughout the early 1990s included multi-modal improvements and the incorporation of an accessibility feedback routine in 1994. The model underwent major validations in the late 1990s and early 2000s to incorporate the 1990 census data and results of the 1997/1998 NJTPA/NYMTC Household Interview Survey.
NJTPA and other agencies continued to use this model for air quality conformity and other planning analyses until 2007 when the newly enhanced model was completed.
Characteristics of the NJRTM model
In its final configuration, the NJRTM area consisted of the thirteen county North Jersey region; external stations were used to represent travel to and from places outside the region including New York City
The NJRTM had 1,377 traffic analysis zones and 74 external stations. The highway network included most arterials (major and minor) including most 500 level county roads but did not include many collector or local roads. There were three separate networks for the three different time periods used for running the model: AM peak (6:30am to 8:30am), PM peak (3:30pm to 6:00pm) and off peak (all other times).
The model had four trip purposes:
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Home Based Work (trips between home and work),
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Home Based Shopping (trips between home and shopping destinations),
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Home Based Other (all other trips from or to home), and
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Non-Home Based (all other trips that has home as neither an origin nor destination, e.g., a trip from work to the movies).
The model had six modes for most trip purposes (seven modes for the Home Based Work trip purpose):
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Driving Alone (SOV),
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Carpooling with 2, 3, or more occupants per vehicle (HOV-2, HOV-3, HOV-4+ (only for Home Based Work)),
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Walking to Transit,
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Driving to Transit, and
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Trucks.
The model’s unique accessibility feedback loop reallocated a small amount of demographic data based on a measure of accessibility for each zone after the first model assignment iteration. This feature served to recognize how settlement and land development patterns orient themselves toward places with good transportation access.