  In the mechanism design theory, a designer would like to implement a desired
social choice function which specifies her favorite outcome for each possible
profile of all agents' types. Traditionally, the designer may be in a dilemma
in the sense that even if she is not satisfied with some outcome with low
profit, she has to announce it because she must obey the mechanism designed by
herself. In this paper, we investigate a case where the designer can induce
each agent to adjust his type in a one-shot mechanism. We propose that for a
profitable Bayesian implementable social choice function, the designer may
escape from the above-mentioned dilemma by spending the optimal adjustment cost
and obtain a higher profit. Finally, we construct an example to show that the
designer can breakthrough the limit of expected profit which she can obtain at
most in the traditional optimal auction model.
