Fredholm representation of multiparameter Gaussian processes with applications to equivalence in law and series expansions✩         
        
    
        Volume 2, Issue 3 (2015): PRESTO-2015, pp. 287–295
            
    
                    Pub. online: 2 October 2015
                    
        Type: Research Article
            
                
             Open Access
Open Access
        
            
    
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                The authors thank the referees for their useful comments.
    
    
                    1
                Lauri Viitasaari was partially funded by Emil Aaltonen Foundation.
    
                Received
25 June 2015
                                    25 June 2015
                Revised
21 September 2015
                                    21 September 2015
                Accepted
21 September 2015
                                    21 September 2015
                Published
2 October 2015
                    2 October 2015
Abstract
We show that every multiparameter Gaussian process with integrable variance function admits a Wiener integral representation of Fredholm type with respect to the Brownian sheet. The Fredholm kernel in the representation can be constructed as the unique symmetric square root of the covariance. We analyze the equivalence of multiparameter Gaussian processes by using the Fredholm representation and show how to construct series expansions for multiparameter Gaussian processes by using the Fredholm kernel.
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