Household Transition Model (HTM)

Objective

The Household Transition Model (HTM) predicts new households migrating into the region, or the loss of households emigrating from the region.

Algorithm

The model compares the total number of households (possibly by type) in the households table at the beginning of a simulation year, to the total number of households (by type) specified by the user in the annual household control totals for that year. If the control total value is higher, the model adds the necessary number of households to the household table by sampling existing households (of the same type) and duplicating them. If the control totals indicate a declining household count (by type) then the appropriate number of households in the data are selected at random and removed. The role of this model is to keep the household data in the simulation synchronized with aggregate expectations of population and households. Note that the model can be configured by the user's choice of specification of the annual control totals. If no household characteristics are included in the control totals, then the synchronization is done for the total number of households. Otherwise it is done by the categories present in the control totals.

OPUS path to model code

urbansim.models.transition_model

Configuration

The configuration of the HTM in the parcel model system is summarized in the following table:

Element	Setting
Agent	Household
Dataset	Household
Model Structure	Rule Based

Data

The following tables are used by the Household Transition Model in the parcel version of UrbanSim.

Table Name	Brief Description
annual_household_control_totals	Annual aggregate control totals for households, optionally by type
households	Synthesized households
persons	Synthesized persons (optional)

-- PaulWaddell - 09 Dec 2009