We discuss the precision with which financial models are handled, in particular optimisation models. We argue that precision is only required to a level that is justified by the overall accuracy of the model, and that this required precision should be specifically analysed, so to better...

A direct method for the solution of large and sparse systems of linear equations is presented. On one hand, the method exploits the qualitative structure of the graph associated to the linear system to reduce the number of elementary operations in the algorithm. On the other hand, the method...