Application of Statistics

Sensitivity analysis helps to understand which of the inputs are critical to the choice of the best decision alternative and how changes in the future events or changes in payoffs affect the recommended decision. If a small change in the value of the inputs causes a big change in the recommended decision alternative, then the solution to the problem is sensitive to the particular input. For example, how many people will quit smoking if a pack of cigarette costs more than $10-none, few or many?

What testing would you be using to solve it ?