We obtain minimax lower bounds on the regret for the classical two-armed bandit problem. We provide a finite-sample minimax version of the well-known log asymptotic lower bound of Lai and Robbins. The finite-time lower bound allows us to derive conditions for the amount of time necessary to make any significant gain over a random guessing strategy. These bounds depend on the class of possible d...

Adults and children have recently been shown to prefer guessing the outcome of a die roll after the die has been rolled (but remained out of sight) rather than before it has been rolled. This result is contrary to the predictions of the competence hypothesis (Heath & Tversky, 1991 ), which proposes that people are sensitive to the degree of their relative ignorance and therefore prefer to guess...

We compared the effects of guessing vs. choosing an upcoming task. In a task-switching paradigm with four tasks, two groups of participants were asked to either guess or choose which task will be presented next under otherwise identical conditions. The upcoming task corresponded to participants' guesses or choices in 75 % of the trials. However, only participants in the Choosing condition were ...