Before revision:  Our algorithm also allows us to quantify the effect of errors in click-through rate estimation on the achieved revenue . We show that we lose at most \frac{\Delta{1+\Delta} fraction of the revenue if \Delta is the percentage error in click-through rate estimation} .
After revision:  Our algorithm also allows us to quantify the effect of errors in click-through rate estimation on the achieved revenue {1+\Delta} fraction of the revenue if \Delta is the percentage error in click-through rate estimation} .