Australian Immigration System Dynamics

This interactive simulation models Australia's permanent immigration system using system dynamics methodology. The model captures complex feedback loops and interdependencies between immigration policy settings and their impacts on housing, healthcare, employment, and infrastructure systems.

Purpose: To provide policymakers, researchers, and the public with a tool to explore the long-term consequences of different immigration policy scenarios in a transparent, evidence-based manner.

The model consists of five interconnected subsystems:

• Immigration Processing: Models visa application flows, processing capacity, and approval rates across four main streams (Skilled, Family, Humanitarian, Other)
• Population Dynamics: Tracks immigrant population stocks, natural increase, and emigration flows
• Housing System: Models housing supply, demand, construction rates, and affordability pressures
• Healthcare System: Tracks healthcare capacity, utilization, workforce, and wait times
• Employment & Economy: Models labor force participation, unemployment, skills matching, and economic contributions

Immigration Parameters:

• Skilled Stream Quota: Annual places allocated to skilled migration (default: 132,200)
• Family Stream Quota: Annual places for family reunion visas (default: 52,500)
• Humanitarian Quota: Refugee and humanitarian places (default: 20,000)
• Processing Capacity: Administrative capacity to process applications (affects delays)

System Capacity Parameters:

• Housing Construction Rate: Annual dwelling completions (baseline: 171,000)
• Healthcare Capacity Growth: Rate of healthcare workforce expansion (baseline: 0.5% annually)
• Infrastructure Investment: Public investment in transport, utilities, and services

Demographic Assumptions:

• Average household size: 2.5 persons per dwelling
• Labor force participation: 75% for skilled migrants, 60% for family stream
• Healthcare utilization: Migrants use healthcare at 80% of domestic rate initially, converging to 100% over 5 years

The model incorporates several important feedback mechanisms:

Balancing Loops (Negative Feedback):

• Housing Affordability: Increased immigration → increased housing demand → higher prices → reduced immigration attractiveness
• Infrastructure Strain: Population growth → service congestion → reduced quality of life → lower immigration appeal
• Processing Delays: High application volumes → longer processing times → application backlogs → reduced effective intake

Reinforcing Loops (Positive Feedback):

• Economic Growth: Skilled immigration → increased productivity → economic expansion → greater immigration capacity
• Network Effects: Established immigrant communities → easier settlement → increased immigration attractiveness
• Skills Development: Immigrant workforce → knowledge transfer → enhanced local skills → competitive advantage

Core Stock-Flow Equations:

Immigrant Population(t) = Immigrant Population(t-dt) + (Immigration Inflow - Emigration - Deaths) * dt

Housing Stock(t) = Housing Stock(t-dt) + (New Construction - Depreciation) * dt

Healthcare Capacity(t) = Healthcare Capacity(t-dt) + (Workforce Growth - Retirements) * dt

Immigration Inflow Calculation:

Immigration Inflow = MIN(Policy Quota, Processing Capacity) * Economic Multiplier * Attractiveness Factor

Housing Demand Pressure:

Housing Gap = (Total Population / Household Size) - Housing Stock

Price Pressure = 1 + (Housing Gap / Housing Stock) * Elasticity

Healthcare Utilization:

Healthcare Demand = Population * Utilization Rate * Age Adjustment

Capacity Utilization = Healthcare Demand / Healthcare Capacity

The model is calibrated using official Australian government data:

• Department of Home Affairs: Immigration statistics, visa grant data, processing times
• Australian Bureau of Statistics (ABS): Population data, housing statistics, labor force surveys
• Australian Institute of Health and Welfare (AIHW): Healthcare workforce and utilization data
• Reserve Bank of Australia (RBA): Economic indicators and housing market data
• Infrastructure Australia: Infrastructure capacity and investment data

Base Year: 2023-24 planning levels are used as the baseline scenario.

The model has been validated through several methods:

• Historical Validation: Model behavior compared against 2010-2023 historical data
• Extreme Conditions Testing: Model tested under extreme parameter values to ensure realistic behavior
• Sensitivity Analysis: Key parameters varied to assess model robustness
• Expert Review: Model structure reviewed by migration policy experts and system dynamics practitioners

Limitations: The model simplifies complex social and economic processes. Results should be interpreted as indicative trends rather than precise predictions. External shocks (e.g., pandemics, economic crises) are not explicitly modeled.

Current Baseline:

Reflects 2023-24 Migration Program planning levels with 185,000 total places. This scenario maintains current policy settings and infrastructure investment levels.

High Skilled Focus:

Increases skilled stream to 180,000 places while reducing family stream to 40,000. Emphasizes economic contribution and addresses skills shortages. Assumes moderate infrastructure investment.

Balanced Growth:

Increases total intake to 220,000 with proportional increases across all streams. Includes enhanced infrastructure investment (20% above baseline) and accelerated housing construction.

Reduced Intake:

Conservative approach with 140,000 total places. Allows infrastructure and services to catch up with demand. Maintains proportional distribution across streams.

Humanitarian Focus:

Increases humanitarian intake to 35,000 places with enhanced settlement services. Includes additional healthcare and social service capacity to support refugee settlement.

Rapid Growth:

Ambitious 250,000 annual intake with significant infrastructure acceleration. Housing construction increased to 240,000 dwellings annually. Requires sustained high investment.

1. Select a Scenario: Start with a pre-configured scenario from the Scenarios tab, or customize parameters in the Simulation tab
2. Adjust Parameters: Use sliders to modify immigration quotas and system capacity parameters
3. Run Simulation: Click "Run Simulation" to execute the model over your chosen time horizon
4. Analyze Results: Review charts and statistics showing impacts on housing, healthcare, employment, and infrastructure
5. Compare Scenarios: Use the Comparison tab to run multiple scenarios side-by-side
6. Export Data: Download results as CSV, JSON, or generate a comprehensive PDF report

What the model shows:

• Long-term trends and patterns in system behavior
• Relative impacts of different policy choices
• Potential pressure points in housing, healthcare, and infrastructure
• Trade-offs between different policy objectives

What the model does NOT show:

• Precise year-by-year predictions (use for directional insights only)
• Social and cultural impacts (focuses on quantifiable system metrics)
• Effects of major external shocks or policy disruptions
• Regional variations within Australia (national-level model)

Best Practices:

• Run multiple scenarios to explore a range of possible futures
• Pay attention to trends and patterns rather than specific numbers
• Consider how feedback loops might amplify or dampen effects over time
• Use comparison tools to understand relative impacts of policy choices

Simulation Engine: Euler integration method with user-configurable time step

Visualization: Chart.js library for interactive charts and graphs

Architecture: Client-side JavaScript implementation (no server required)

Browser Compatibility: Modern browsers with ES6 support (Chrome, Firefox, Safari, Edge)

Performance: Optimized for simulations up to 50 years with quarterly time steps

• Sterman, J.D. (2000). Business Dynamics: Systems Thinking and Modeling for a Complex World. McGraw-Hill.
• Department of Home Affairs. (2023). Migration Program Planning Levels. Australian Government.
• Productivity Commission. (2016). Migrant Intake into Australia. Australian Government.
• Australian Bureau of Statistics. (2023). Migration, Australia. Catalogue 3412.0.
• Forrester, J.W. (1961). Industrial Dynamics. MIT Press.

This model is provided for educational and policy analysis purposes. For questions, feedback, or to report issues, please contact the development team.

Version: 1.0.0
Last Updated: December 2024
License: Educational use