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CPS1145 Adeniji Oyebimpe Emmanuel et al.
                The  generalized  beta  distribution  of  the  first  kind  was  introduced  by
            McDonald (1984), with link function
                                                                                      (7)


                Where a, b, c are the shape parameter, f(y) is the probability function of
            student –t distribution, F(y) is the incomplete beta function and g(y) is the link
            function  of  Generalized  Beta  Skew-t  distribution.  The  log-likelihood  for
            estimation is:




                                                                                (8)

            Fisher (1934) introduce the concept of weighted distribution, w(y) be a non–
            negative weighted function satisfying
                µw = E(w(y)) <∞ then the random variables of Yw having pdf




                Where                      E(w(y))= -∞< y < ∞
            is  said  to  have  weighted  distribution.  length  biased  distribution  is  derived
            when the weighted function depend on the length of units of interest (i.e. w(y)
            = y). The pdf of a length biased random variable is defined as:

                                                                                     (9)
            The log-likelihood of equation (4) when the pdf is student-t is obtained as

                                                                                    (10)


                These two newly distributions will be incorporated into conventional and
            Jumps GARCH models. In the literature the most recent error innovation used
            along  with  volatility  models  are  Normal,  Student-t  and  GED.  Below  are
            parameter  estimations  of  the  three  innovation:  see  Yaya  et  al,  (2013),  for
            Normal distribution, the Log-likelihood is


                                                                               (11)



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