Relatore: 
          Leonard P. Bos
          
            - Department of Mathematics and Statistics, University of Calgary (Canada)
          
          
 
    
      martedì 21 giugno 2005
      
              alle ore
              17.30 
      
      
       ore 17.00, te caffe` & C.
            
  
 
     
  We consider a risky asset following a mean-reverting stochastic process
of the form
$$dS=\alpha(L-S)dt+\sigma S dW.$$
We show that the (singular) diffusion equation which gives the value
of a European option on $S$ can be represented, upon
expanding in Laguerre polynomials, by a tridiagonal infinite matrix.
We analyse this matrix to show that the diffusion equation does
indeed have a solution and truncate the matrix to give a simple,
highly efficient method for the numerical calculation of
the solution.