%-------------------------------------------------------------------------------
% UF Sparse Matrix Collection, Tim Davis
% http://www.cise.ufl.edu/research/sparse/matrices/Marini/eurqsa
% name: Marini/eurqsa
% [Economic time series reconciliation; Di Fonzo (Univ Padua) & Marini (ISTAT)]
% id: 1891
% date: 2008
% author: T. Di Fonzo, M. Marini
% ed: T. Davis
% fields: name title A id date author ed kind b notes
% kind: economic problem
%-------------------------------------------------------------------------------
% notes:
% Economic statistics are often published in the form of time series, as a   
% collection of observations sampled at equally-spaced time periods (months, 
% quarters). Economic concepts behind such statistics are often linked by a  
% system of linear relationships, deriving from the economic theory. However,
% these restrictions are rarely met by the original time series for various  
% reasons.  Then, data sets of real-world variables generally show           
% discrepancies with respect to prior restrictions on their values.  The     
% adjustment of a set of data in order to satisfy a number of accounting     
% restrictions -and thus to remove any discrepancy -is generally known as    
% the reconciliation problem.                                                
%                                                                            
% The matrix comes from a real application composed of 183 quarterly time    
% series observed over 28 quarters, which form the system of European        
% national accounts by institutional sectors (EURQSA). Then, the number of   
% observations to be reconciled is n = 28 x 183 = 5124. The variables are    
% connected by a system of 30 linear relationships. Moreover, each quarterly 
% time series must be in line with the same variables observed yearly (due   
% to different compilation practices quarterly and annual estimates might    
% differ). The total number of constraints of the system is k = 2121. On     
% the whole, matrix A has dimension 7245, with block (1,1) of dimension 5124.
%-------------------------------------------------------------------------------
