SimPaths

SimPaths is an open-source framework for modelling individual and household life course events. The framework is designed to project life histories through time, building up a detailed picture of career paths, family (inter)relations, health, and financial circumstances. The modular nature of the SimPaths framework is designed to facilitate analysis of alternative assumptions concerning the tax and benefit system, sensitivity to parameter estimates and alternative approaches for projecting labour/leisure and consumption/savings decisions. SimPaths builds upon standardised assumptions and data sources, which facilitates adaptation to alternative countries – models based on the framework currently exist for the UK, Greece, Hungary, Italy, and Poland, and are under development for Germany, Spain and Sweden.

All source code is freely available for download under a European Free/Open Source Software (F/OSS) EUPL-1.2 license, alongside evolving, increasingly detailed documentation. The framework incorporates many state-of-the-art features which are rarely combined in dynamic models:

  • SimPaths generates data for a diverse range of life course domains – education, work, family life and health – explicitly modelling the dynamic feedback effects between them.
  • SimPaths is linked to an underlying tax-benefit model, which provides a realistic description of the impact of taxes and benefits at both the individual and population level. The detailed tax-benefit description that reflects prevailing public policy is important for any evaluation of the funding and distributional implications of population ageing for the welfare state.
  • SimPaths features rich behavioural models over the principal economic margins of decision making (time-use and savings), where projected choices depend not only on individual characteristics, but also on the influence of fiscal incentives on future expectations.
  • From an architectural perspective, SimPaths is built following a highly modular approach. This facilitates switching between alternative methods for projecting behaviour to allow for sensitivity and robustness analysis. The model is written in Java, using the JAS-mine suite of simulation libraries.
  • SimPaths is built with an eye to facilitate adaptation to different countries. This is achieved by decoupling the dynamic structure from the tax-benefit model, so that alternative tax-benefit systems can be easily interchanged within the model. Furthermore, care has been taken to describe model dynamics that can be estimated on a single standardised data source for European Union countries (Statistics on Income and Living Conditions, EU-SILC).

SimPaths GitHub repository

https://github.com/centreformicrosimulation/SimPaths (including source code, documentation, how-to guides and video tutorials)

Reference paper

Bronka P, van de Ven J, Kopasker D, Katikireddi SV, Richiardi M, (2024). SimPaths: an open-source microsimulation model for life course analysis. International Journal of Microsimulation, 18(1): 95-133.

Please use the reference above if you use SimPaths or derived work.

Further references

UK model

EU models