[1] Institute of Statistics and Mathematical Economics,
[2] University of Karlsruhe,undefined
[3] D-76128 Karlsruhe,undefined
[4] Germany (e-mail: rachev@lsoe.uni-karlsruhe.de),undefined
[5] Department of Statistics and Applied Probability,undefined
[6] University of California,undefined
[7] Santa Barbara,undefined
[8] CA 93106,undefined
[9] USA (e-mail: seonkoon@pstat.ucsb.edu),undefined