kep-solver 1.0.0

A Python package for reading and solving single instances of kidney exchange problems.

kep_solver

This Python package is devoted to various algorithms, procedures and mechanisms that are useful when studying kidney exchange programmes in general. It is written and maintained by William Pettersson [e-mail]

Current features

• Reading instance files (json and XML formats)

• Creation of compatibility graphs

• Solving for the following objectives (single, or hierarchical)

  • Maximise the number of transplants
  • Maximise the number of backarcs
  • Maximise the number of effective 2-way exchanges
  • Minimise the number of three-cycles
  • Maximise the score using the UK scoring mechanisms

While the above objectives are exactly those in use by NHSBT when running the UKLKSS (the UK national KEP), I do intend to add further objectives

Expected users

I see two classes of users of this software:

• Researchers - Depending on what questions you want answered, you can either test policy changes to determine how they affect the running of a KEP, or you can implement new models or objectives to see how they perform
• Health care institutes - I have tried to make this software as robust as possible, but for now I cannot guarantee any particular level of performance or any exact optimality of a solution. If you do want to use this software for real-world impact, feel free to get in touch and I may be able to help.

Interface

This is just a Python module for now, there is no interface for using it that does not involve writing Python code. I do have the basics of a web interface ready, but it's not published yet as I want to make it more robust and clean first.

Future plans

Note that some of these are easier than other, and there is no timeline on when any will be developed

• Random instance generation
• Simulating the development of a KEP over time
• Supporting transnational pools

Contributing

I'm still not sure what the best way to move forward with contributors is. Currently I own all of the IP, so I can license this software to other health organisations if they have specific requirements. However, if anyone contributes code I may lose this ability. I am pondering having an organisation "own" the code specifically so we can re-license to national health organisations or similar.