On exponential functionals of processes with independent increments
    
    
  
  
  
      
      
      
        
Teoriâ veroâtnostej i ee primeneniâ, Tome 63 (2018) no. 2, pp. 330-357
    
  
  
  
  
  
    
      
      
        
      
      
      
    Voir la notice de l'article provenant de la source Math-Net.Ru
            
              			In this paper, we study the exponential functionals of the processes $X$ with independent increments, namely,
$I_t= \int_0^t\exp\{-X_s\}\,ds,\ t\geq 0$,
and also
$I_{\infty}= \int_0^{\infty}\exp\{-X_s\}\,ds$.
When $X$ is a semimartingale with absolutely continuous characteristics, we
derive necessary and sufficient conditions for the existence of the Laplace
exponent of $I_t$, and also the sufficient conditions of finiteness of the
Mellin transform $\mathbf{E}(I_t^{\alpha})$ with $\alpha\in \mathbf{R}$. We give
recurrent integral equations for this Mellin transform. Then we apply these
recurrent formulas to calculate the moments.
We also present the corresponding results for the exponential functionals of
Lévy processes, which hold under less restrictive conditions than in
[J. Bertoin and M. Yor, Probab. Surv., 2 (2005), pp. 191–212]. In
particular, we obtain an explicit formula for the moments of $I_t$ and
$I_{\infty}$, and we give the precise number of finite moments of $I_{\infty}$.
			
            
            
            
          
        
      
                  
                    
                    
                    
                        
Keywords: 
exponential functional, process with independent increments, Lévy process, Mellin transform
Mots-clés : moments.
                    
                  
                
                
                Mots-clés : moments.
@article{TVP_2018_63_2_a5,
     author = {P. Salminen and L. Vostrikova},
     title = {On exponential functionals of processes with independent increments},
     journal = {Teori\^a vero\^atnostej i ee primeneni\^a},
     pages = {330--357},
     publisher = {mathdoc},
     volume = {63},
     number = {2},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TVP_2018_63_2_a5/}
}
                      
                      
                    TY - JOUR AU - P. Salminen AU - L. Vostrikova TI - On exponential functionals of processes with independent increments JO - Teoriâ veroâtnostej i ee primeneniâ PY - 2018 SP - 330 EP - 357 VL - 63 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TVP_2018_63_2_a5/ LA - en ID - TVP_2018_63_2_a5 ER -
P. Salminen; L. Vostrikova. On exponential functionals of processes with independent increments. Teoriâ veroâtnostej i ee primeneniâ, Tome 63 (2018) no. 2, pp. 330-357. http://geodesic.mathdoc.fr/item/TVP_2018_63_2_a5/
