We explore some little investigated aspects of the well known
betting scheme defining coherent lower or upper previsions in terms of
admissible gains. A limiting situation (lose-or-draw) where the supremum
of some gain is zero is discussed, deriving a gambler’s gain evaluations
and comparing the differences between the imprecise and precise prevision
cases. Then, the correspondence of the betting scheme for imprecise
previsions with real-world situations is analysed, showing how the gambler’s
profit objectives may compel him to select certain types of bets.
