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STS518 B.H. Jasiulis G. et al.
                  ()/() →   in the sense of distribution. We denote the inverse of () by
                  () and  then U є  1/( − ) . Clearly ()/() →   implies  that (())/
                    →  .
                  Now we have




                  Since  V(U(n)t)/n ⁓ V(U(n))   −  /n  → t α – θ ,  we  have  P( ≤ U(n)t ) →
                                                                                
                  P( Z ≥ t α – θ ) = P( Z −1/( α − θ  ) ≤ t).
                  Finally we conclude that  /U(n) → Z −1/( α − θ )  in the sense of distribution.
                                            
                  The construction shows that (()) ⁓ (()) ⁓ , which ends the proof. □

                  It is worth to notice that exponential transform of random variable X fit to
                  maximal daily concentration of nitrogen dioxide for data from USA and Poland
                  in some cases. Above stable distributions are infinitely divisible in the Kendall
                  generalized convolution algebra.
                  Since random walks with respect to the generalized convolutions form a class
                  of extremal Markov chains (see [1, 5, 10]), studying them in the appropriate
                  algebras will be a meaningful contribution to extreme value theory.
                  More about regular variation context for extremal Markov chains driven by the
                  Kendall convolution one can find in [1, 10].

                  4. Discussion and Conclusion:
                     Even though the family of generalized convolutions is pretty rich by now
                  we are still interested in constructing new examples and finding new methods
                  of constructing them on the base of these which we already know.
                     The next open problem lie on proposing a statistical methods to recognize
                  which  stochastic  processes  are  the  Lévy  processes  with  respect  to  some
                  generalized convolution. Could we recognize this generalized convolution on
                  the base of some empirical data?

                  Acknowledgements.  This  paper  is  a  part  of  project  "First  order  Kendall
                  maximal autoregressive processes and their applications", which is carried out
                  within  the  POWROTY/REINTEGRATION  programme  of  the  Foundation  for
                  Polish  Science  co-financed  by  the  European  Union  under  the  European
                  Regional Development Fund.

                  References
                  1.  Arendarczyk M., Jasiulis-Gołdyn  B.H. & Omey E.A.M. (2019). Asymptotic
                      properties of Kendall random walks, submitted, arXiv:
                      https://arxiv.org/pdf/1901.05698.pdf




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