ABSTRACT
This chapter is devoted to characterization problems. The main em phasis is on characterizing distributions,or families of distribution, by properties associated with products of independent random vari ables. However, we include some classical characterization results partly for historical reason and partly as tools for making our new characterization results complete. For several extensions and for fur ther references we recommend the now classical books by Linnik and Rao [90], Galambos and Kotz [61], Azlarov and Volodin [13] and Kakosyan, Klebanov and Melamed [91]. Several recent conference proceedings and special issues of periodicals also deal with this sub ject matter, which we do not include here. These are specified in the subsections of the present chapter.
