eBarter is based on the idea of "economic tension":

Economic tension of a trade

For a trade where:
* transactions are defined as:
    "a quantity sold <=QS of one good in exchange of an other quantity baught >=QB of an other good"
* participants link transactions where they are buyer of one and seller of an other, and where values are expressed with the same kind of good,
* transactions form a loop of commitments,
the economic tension of the trade is the product of all QS divided by the product of all QB.

When the economic tension is <=1, the trade can be accepted by all participants and when it is <1, it produces a gain for all participants of the trade.

What is ebarter

eBarter is a tool that searches for loops of commitments and distributes fairly the gain of the trade between participants.
The gain of a trade is expressed for each participant as a quantity of the good he used to express the values of it's transactions where he was buyer and seller.

eBarter makes a preference to loops having the weakest economic tension - trades where participants have the weakest economic requirements - those who are the most generous.

A detailed explanation is given in this paper on how the gain is distributed and how the loops are detected.

What is it for

eBarter could be used as a barter system or:
As a clearing system for social money; empowering them by allowing economic exchanges between their boudaries, 
At an international level, when the money used make the economy unfair.

Road Map

The clearing algorithm is now implemented in python language with a MySQL database. We think that it can manage more than 30 000 participants.

What remains to do:
Detailed requirements need to be written for the web interface, account management, security and installation.
The product, that should be easily installable, easy to use and reliable.

How can you help

You can donate for the project, and contributions are welcome.

copyritgh 2005 Olivier Chaussavoine