How the Model Works

Model:

Overview
1. How the Model Works
2. Use the Model
3. Variable and Input Explanations
4. Frequently Asked Questions
5. Examples

1. How the Model Works

Vehicle Ownership Model

Below is an outline of how the Vehicle Ownership Model works. The model is based on statistical research done by the Institute for Location Efficiency.

Factors Impacting Vehicle Ownership	Rationale	Development Characteristic Used for Input	Explanation	Specific Variable Used
Income	Higher income increases average vehicle ownership rates	Rent	With deed-restricted affordable housing, annual rent is 30% of household income.	Income per Person ($/P)
Household Size	Larger households own more vehicles	Bedrooms	Household size increases with bedrooms	Persons per Household (P/H)
Neighborhood Density	Density increases proximity to jobs, neighborhood services, parking costs, walk and bike friendliness, decreasing vehicle ownership	Location	Project location will have specific neighborhood density	Households per Residential Acre (H/RA)
Neighborhood Transit Access	Quality transit reduces need for vehicles	Location	Project location will have specific transit access	Transit Accessibility Index (TAI)

Vehicle Miles Traveled (VMT) Model

Factors Impacting Vehicle Miles Traveled	Rationale	Development Characteristic Used for Input	Explanation	Specific Variable Used
Income	Higher income increases average vehicle ownership rates	Rent	With deed-restricted affordable housing, annual rent is 30% of household income.	Income per Person ($/P)
Household Size	Larger households make more frequent vehicle trips	Bedrooms	Household size increases with bedrooms	Persons per Household (P/H)
Neighborhood Density	Density increases proximity to jobs, neighborhood services, parking costs, walk and bike friendliness, decreasing distance and frequency of trips	Location	Project location will have specific neighborhood density	Households per Total Acre (H/TA)
Neighborhood Pedestrian Bicycle Friendliness	Walking and cycling reduce vehicle trips and miles traveled	Location	Project location will have specific Ped friendliness	Pedestrian/Bicycle Friendliness (Ped)
Vehicles Owned	More vehicles per household will increase vehicle miles traveled	Vehicle Ownership Model	Vehicle ownership computed from above model	Vehicles per Household (Veh/HH)

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