How many stars would you have to search before you would expect to hear a signal?

The number of stars you would need to search before expecting to hear a signal depends on several factors, including the density of stars in the region, the likelihood of intelligent civilizations existing, and the duration and strength of their signals. Estimates from projects like the Drake Equation suggest that, within our galaxy, you might expect to find a signal after searching thousands to millions of stars, depending on the assumptions made about the parameters involved. Thus, it is a complex calculation, but many scientists believe that even with extensive searching, contact may still be rare.