One of the ways to make reinforcement learning (RL) more ef-
ficient is by utilizing human advice. Because human advice is
expensive, the central question in advice-based reinforcement
learning is, how to decide in which states the agent should ask
for advice. To approach this challenge, various advice strate-
gies have been proposed. Although all of these strategies dis-
tribute advice more efficiently than naive strategies (such as
choosing random states), they rely solely on the agent’s inter-
nal representation of the task (the action-value function, the
policy, etc.) and therefore, are rather inefficient when this rep-
resentation is not accurate, in particular, in the early stages of
the learning process. To address this weakness, we propose an
approach to advice-based RL, in which the human’s role is not
limited to giving advice in chosen states, but also includes hint-
ing apriori (before the learning procedure) which sub-domains
of the state space require more advice. Specifically, we sug-
gest different ways to improve any given advice strategy by
utilizing the concept of critical states: states in which it is very
important to choose the correct action. Finally, we present ex-
periments in 2 environments that validate the efficiency of our
approach.