Although game theory would seem to be the natural mathematical discipline for the study of poker, a number of other specific mathematical problems arising from the game have also been studied.
Many of these are only tangentially related to the core problems being addressed by strategic game playing, but are still worth looking at, if only for the sake of completeness. Two Japanese mathematicians, Minoru Sakaguchi and Setsuko Sakai, are responsible for most of the work on these loosely related topics. Some of the problems they have looked at include the effects of partial information [68, 72, 73, 74], multi-stage poker [69, 75], the disadvantage of being the first player to act in a given betting round [70], and a few of the subtleties encountered with more realistic poker models [71, 77]. Notwithstanding the highly specialized nature of these problems, a few of their mathematical ideas might be incorporated into algorithmic analysis techniques. More optimistically, the purely mathematical approach may eventually produce some tangible dividends for poker practitioners. For example, in one of their most recent articles, Sakaguchi and Sakai solve (from a purely mathematical standpoint) some of the fundamentally difficult problems in three-person playing scenarios [76].
While these papers may be of limited practical value, it is important to maintain a mathematically precise view of the game. Toward this end, some background in probability theory is essential for academic poker researchers. While this knowledge can be acquired in many ways, one strongly recommended reference is ``The Theory of Gambling and Statistical Logic'', by Richard Epstein [33].