Feature Comparison
This document compares the features of the NZ-Microsim library with the original SAS models it is based on, as well as two other popular open-source microsimulation platforms: PolicyEngine and OpenFisca.
| Feature | NZ-Microsim (This Repo) | Original SAS Models | PolicyEngine | OpenFisca |
|---|---|---|---|---|
| Core Focus | New Zealand tax and transfer system | New Zealand tax and transfer system | Multi-country tax and benefit systems | Generic microsimulation framework ("Legislation as code") |
| Technology | Python | SAS | Python | Python |
| Open Source | Yes (Apache 2.0 License) | Yes (MIT License) | Yes (AGPL-3.0) | Yes (AGPL-3.0) |
| Core Engine | Custom-built | Custom-built | PolicyEngine Core (fork of OpenFisca-Core) | OpenFisca-Core |
| Modularity | Modular design with pluggable components | Macro-based (famsim) |
Highly modular (core engine + country packages) | Highly modular (core engine + country packages) |
| Country Coverage | New Zealand only | New Zealand only | US, UK, Canada | France, Spain, Senegal, and others |
| Web Interface | No | No | Yes (React-based web app) | Yes (via country packages) |
| API | No | No | Yes (REST API) | Yes (REST API) |
| Parameterisation | JSON files per tax year | Hardcoded in macros, with some input parameters | YAML files | YAML files |
| Key Features | - Income Tax - Working for Families (WFF) - FamilyBoost - IETC - RWT - Superannuation - Reporting & Sensitivity Analysis |
- Income Tax - Working for Families (WFF) |
- Detailed tax and benefit calculations for each country - Microdata generation - Extensible with new policies |
- Core calculus engine - Domain-specific language for policy rules - Handles complex dependencies between variables |
| Extensibility | Designed to be extensible | Limited | Designed to be extensible through new country packages or policies | Designed to be extensible through new country packages or policies |
| Tax Year Coverage | 2005-2025 | Not specified | Varies by country | Varies by country |
| Community | Small, focused on this project | Internal to Inland Revenue | Active community | Active community |