Case study 02 · Coupled simulation

FLOODABM

A 52,141-household agent-based model coupled to catastrophe, insurance, and financial mechanics across 27 New Jersey census tracts.

  • 52,141 households
  • 27 census tracts
  • 2011–2023
  • 50 stochastic runs per scenario

Why this problem matters

Flood adaptation decisions change losses unevenly across households. A useful model must connect behavioral pathways to hazard, property, insurance, and out-of-pocket outcomes over time.

How I approached it

I designed and fielded the 937-household survey, translated pathways into agent parameters, built the household simulation, and coupled it to catastrophe and NFIP mechanics.

What it contributes

Coupling behavior to physical and financial feedback makes assumptions auditable and exposes where a seemingly reasonable action creates uneven consequences.

For AI teams, FLOODABM is a stateful evaluation environment: decisions update an external system, consequences accumulate, and model assumptions remain visible.

System artifact

Inspect the research logic

The AGU 2025 poster and archived repository document the coupled architecture and aggregate outcomes.

Decision Observatory

Evidence enters. Decisions stay inspectable.

Synthetic example
Interpret the hazard signal.
Agent decision
Install a temporary barrier
Contents protection
Not applied
Hazard level
3Unchanged by household action
Resource tokens
6

A homeowner can protect the building; the river hazard stays unchanged.

Levels and tokens are synthetic units; not FLOODABM outputs.

Interactive controls require JavaScript. The complete flow and sources remain below.

Evaluation

  1. Human evidence

    Measured constructs and reported choices establish the empirical reference.

    Published evidence
  2. Context

    A label-blind synthetic profile carries only approved attributes into the prompt.

    Illustrative example
  3. LLM proposal

    Repeated model runs produce a choice and a concise rationale for comparison.

    Illustrative example
  4. Validation / repair

    Checks compare direction, subgroup behavior, and run-to-run stability without exposing respondent records.

    Public artifact
  5. Consequence

    The result becomes an evaluation finding, not a claim that the model represents a person.

    Illustrative example
Inspect the complete case

Governance

  1. Human evidence

    Behavioral and physical constraints define what a plausible action must respect.

    Published evidence
  2. Context

    A synthetic agent state limits the actions the model may propose.

    Illustrative example
  3. LLM proposal

    The LLM returns a structured proposal rather than mutating the simulation directly.

    Illustrative example
  4. Validation / repair

    Validators reject invalid fields, request targeted repair, and retain an audit trace.

    Public artifact
  5. Consequence

    Only an accepted proposal updates the coupled model state.

    Illustrative example
Inspect the complete case

Simulation

  1. Human evidence

    Survey evidence and public flood-risk sources ground household behavior.

    Published evidence
  2. Context

    Household tenure, risk perception, resources, and exposure form the decision context.

    Published evidence
  3. Agent decision

    Agents choose adaptation, insurance, or no action under modeled constraints.

    Public artifact
  4. Validation / repair

    Model checks keep behavioral, financial, and physical state transitions consistent.

    Public artifact
  5. Consequence

    Flood losses and adaptation alter the household and environmental state for the next cycle.

    Published evidence
Inspect the complete case
Research context and method

Illustrative system architecture · not a reported study result

Coupled human and environmental feedbackTwo connected tracks show human interpretation and adaptation above environmental hazard, damage, and state updates below.

Human track

  1. 01Perceive risk
  2. 02Decide and adapt
  3. 03Update resources

Environment track

  1. 01Hazard state
  2. 02Damage and loss
  3. 03Next environment

What changes in this lensOwner state includes property adaptation, insurance, damage, payout, and out-of-pocket feedback.

Method in detail

  1. Survey-ground behavioral parameters through SEM and Bayesian calibration.
  2. Advance household adaptation and insurance decisions over annual time steps.
  3. Couple agents to flood hazard, property damage, NFIP premium/payout/deductible, and financial state.
  4. Run 50 stochastic realizations for each scenario and report aggregate distributions.

Validation and limitations

Validation

  • Survey-grounded behavioral parameters
  • Scenario ensembles
  • Multi-level diagnostics
  • Archived code and citation metadata

Limitations

  • Calibration and survey evidence are place- and period-specific.
  • Household agents simplify decision processes and social context.
  • Hazard and financial outputs inherit uncertainty from coupled models.
  • Scenario results should not be treated as forecasts for an individual household.

Evidence slice

From question to consequence

01Problem
Individual adaptation choices can change long-run flood losses, insurance, and household capacity.
02My role
I developed and tested the household decision layer and coupled it to catastrophe-model state transitions.
03Input
Survey-grounded behavior, household context, flood hazard, damage, insurance, and financial state.
04Decision
Households evaluate protection, insurance, or no action under tenure and resource constraints.
05Validation
Behavioral calibration, state invariants, repeated scenarios, and comparison with public evidence.
06Consequence
Each annual decision changes exposure, loss, and the resources available for the next cycle.

SourcesWater Resources Research articleFLOODABM repository

Contact

Build evaluations that connect model behavior to real evidence

Interested in evaluating AI decisions or building evidence-linked research systems? I welcome research and open-source collaboration, and Summer 2027 internship conversations.

More about my research path