Appendix Table A.1
Detailed Definition of Variables used in BAYCAST Travel Demand Models
(in alphabetical sort order)
Variable Name Model(s) Definition
AreaDeni NHBMC Area Density, zone of production, ((TOTPOP + 2.5 * TOTEMP) / (CIACRE + RESACRE))
Auto Distance HBWDT Door-to-Door Drive Alone Peak Period Distance, in miles
Auto Distance^2 HBWDT Door-to-Door Drive Alone Peak Period Distance, in miles, squared
Berkeleyi HBCOLM Berkeley zones, zone of production (zones=718-722, 725-738, 741-747)
Berkeleyj multiple Berkeley zones, zone of attraction (zones=718-722, 725-738, 741-747)
Bike Time HBCOLM Bicycle travel time, in minutes
Bridge Dummy HBWDT Bridge crossing dummy variable (if Drive Alone Toll > 0.0, then Dummy=1)
CIACRE multiple Commercial + Industrial Acres (ABAG Land Use)
Constant multiple Modal or Utility intercept.
Corej multiple Core zone of work (see Table A.2 for definition of CORE)
Cost multiple Trip Cost in 1990 cents (per person)
CTFT HBWDT Congested Time less Free-Flow Time, in minutes
GPOPD-Leg 1 WHHAO Gross Population Density (TOTPOP/TOTACRE), MIN(10.0,GPOPD)
GPOPD-Leg 2 WHHAO Gross Population Density (TOTPOP/TOTACRE), MAX(0,MIN((GPOPD-10.0),20.0))
GPOPD-Leg 3 WHHAO Gross Population Density (TOTPOP/TOTACRE), MAX(GPOPD-30.0)
HH Income HBWDT Household Income in 1989 constant dollars (not divided by 1000)
HH Size WHHAO Persons per Household (same as Pers/HH)
HHINC multiple Income in 1000s of 1989 dollars (same as Income)
Income HBSRMC Household Income in 1000s of 1990 dollars.
Income-Leg 1 multiple Income in 1989 dollars. MIN(Income,25000)
Income-Leg 2 multiple Income in 1989 dollars. MAX(0,MIN(Income-25000),50000))
IVTT multiple In-Vehicle Travel Time
Ln Net ResDensI HBCOLM Natural Log of Net Residential Density, zone of residence, Ln(TOTHH/RESACRE)
LnAreaDeni HBSHMC Natural Log of Area Density, Zone of Residence (see Table A.2)
LnCost multiple Natural Log of Trip Cost in 1990 cents (per person)
LnEmpDi HBWMC Natural Log of Gross Employment Density, Zone of Residence, Ln(TOTEMP/TOTACRE)
LnEmpDj HBWMC Natural Log of Gross Employment Density, Zone of Work, Ln(TOTEMP/TOTACRE)
LnIncome HBSRMC Natural Log of Household Income in 1000s of 1990 dollars.
LnPHH HBSHMC Natural Log of Household Size
MFDU WHHAO Multi-Family Dwelling Unit Dummy Variable
Multi-Wrkr/HH HBWMC Multiple Number of Workers in Household Dummy Variable
Net ResDensI HBHSM Net Residential Density, Zone of Residence, (TOTHH/RESACRE)
No VHH HBWMC No Vehicle in Household Dummy Variable
OVTT multiple Out-of-Vehicle Travel Time
PaloAltoi HBCOLM Palo Alto zones, zone of production (zones=234-238, 245-248, 254-258)
PaloAltoj multiple Palo Alto zones, zone of attraction (zones=234-238, 245-248, 254-258)
Pers/HH multiple Persons per Household (same as PHH)
PHH multiple Persons per Household (same as Pers/HH)
PHH^3 HBGSM Persons per Household, cubed (polynomial transformation)
RESACRE multiple Residential Acres (ABAG Land Use)
Retail Industry HBWDT Retail Industry worker Dummy Variable
Rurali HBGSM Rural zone of residence (see AREATYPE, Table A.2)
SFOBB WB HBWDT Bay Bridge Westbound Dummy Variable (based on origin & destination zones)
SHPOP62+ WHHAO Share of Population Age 62+
Single VHH HBWMC Single Vehicle in Household Dummy Variable
SR Dummy HBWDT Shared Ride 2+ choice, dummy variable
Stanfordi HBCOLM Stanford zones, zone of production (zones=244, 249-252)
Stanfordj multiple Stanford zones, zone of attraction (zones=244, 249-252)
Theta(Group) multiple Nesting, or Scaling Parameter for Group submode choice nested logit
Theta(Motor) multiple Nesting, or Scaling Parameter for Motorized submode choice nested logit
Theta(Transit) HBWMC Nesting, or Scaling Parameter for Transit submode choice nested logit
Time (Total) HBSHMC Total Travel Time, in minutes
TOTACRE multiple Total Acres (ABAG Land Use)
Veh/HH multiple Vehicles Available per Household (same as VHH)
VHH multiple Vehicles Available per Household (same as Veh/HH)
Wait multiple Transit wait time, in minutes
Walk multiple Walk time, in minutes (may include walk-only utility walk time)
Wrkr/HH HBWMC Workers in Household (same as WHH)
ZVHH multiple Zero-Vehicle Household Dummy Variable (same as Zero VHH)
ZWHH multiple Zero-Worker Household Dummy Variable (same as Zero WHH)

Source: Travel Demand Models for the San Francisco Bay Area (BAYCAST-90). Technical Summary. Metropolitan Transportation Commission, Oakland, California, June 1997.