Incorrect origin TAZ for non-home tours in 2 zone models #1099

There was a bug found in the identification of origin TAZs in at-work subtours. The at-work subtour’s MAZ origin was already identified correctly. The bug was in the derived TAZ used for two-zone destination presampling.

The bug was discovered in the SANDAG at-work subtour destination model. It correctly configures both ORIG_ZONE_ID and CHOOSER_ORIG_COL_NAME as workplace_zone_id. The merged chooser table at this model retained a TAZ representing the traveler’s home. The code reused that column instead of mapping workplace_zone_id to the correct origin TAZ. Consequently, at-work subtours could use:

• the correct workplace MAZ as their configured origin, but
• the traveler’s home TAZ as the coarse origin used for TAZ-level presampling.

PR #1094 now always maps the configured origin MAZ to its TAZ, replacing any unrelated same-named TAZ column.

Regression impact

In the 100-household SANDAG test model:

• 16 of the 23 at-work subtours receive corrected destination_logsum values.
• The modeled origins and chosen destinations remain unchanged.
• One of the 229 tour logsums differs enough to exceed the regression tolerance, causing test to fail.
• Both test_sandag_abm3_progressive[False] and [True] fail on final_tours.csv.
• The failure is limited to the destination_logsum column.

See the [failing ActivitySim CI job](https://github.com/ActivitySim/activitysim/actions/runs/30858703676/job/91836994032).

Required SANDAG updates

1. Regenerate test/regress/final_tours.csv with an ActivitySim revision containing the fix. All corrected at-work logsum values should be accepted, rather than updating only the one value that currently exceeds the comparison tolerance.

2. Refresh the two reference pipelines:

   • reference-pipeline-hh100.parquetpipeline
   • reference-pipeline-hh100-recode.parquetpipeline

   Their existing rtol=1e-4 comparison tolerates the changes, so they are not causing the red CI result, but their at-work destination checkpoints still represent the old calculation.

3. After ActivitySim Deprecate SIMULATE_CHOOSER_COLUMNS and LOGSUM_CHOOSER_COLUMNS settings #1094 is merged, refresh uv.lock so standalone SANDAG environments resolve an ActivitySim commit containing the fix.

No changes are expected to the at-work destination specification, coefficients, ORIG_ZONE_ID, or CHOOSER_ORIG_COL_NAME.

cc @bhargavasana