It is an interface for open source economic modeling of tax policy analysis. It has been developed by the Open Source Policy Center of the American Enterprise Institute.
You can use TaxBrain to model any number of tax policy parameters and their budgetary and economic effects.
The aim of the Open Source Policy Center is to break open the black box of policy modeling that takes place in our nation’s capital, where data and analytics are often obscure and hidden.
The center’s aim is “making policy analysis more transparent, accessible, and innovative by harnessing open source methods to build cutting edge economic models and a webapp for accessing those models.”