Generalized Space Time Fractional Skellam Process

Abstract: This paper introduces the Generalized Space-Time Fractional Skellam Process (GSTFSP) and the Generalized Space Fractional Skellam Process (GSFSP). We investigate their distributional properties including the probability generating function (p.g.f.), probability mass function (p.m.f.), fractional moments, mean, variance, and covariance. The governing state differential equations for these processes are derived, and their increment processes are examined. We establish recurrence relations for the state probabilities of GSFSP and related processes. Furthermore, we obtain the transition probabilities, $n^{th}$-arrival times, and first passage times of these processes. The asymptotic behavior of the tail probabilities is analyzed, and limiting distributions as well as infinite divisibility of GSTFSP and GSFSP are studied. We provide the weighted sum representations for these processes and derive their characterizations. Also, we establish the martingale characterization for GSTFSP, GSFSP and related processes. In addition, we introduce the running average processes of GSFSP and its special cases, and obtain their compound Poisson representations. Finally, the p.m.f. of GSTFSP and simulated sample paths for GSTFSP and GSFSP are plotted.