托福口语 Task 3

The concept of 'signaling theory' in economics suggests that in situations of asymmetric information, one party can send a credible signal to convey hidden qualities, thereby reducing uncertainty. A signal is effective only if it is costly or difficult to fake, ensuring that only high-quality individuals or products can afford to send it. This theory is often applied to markets where buyers and sellers have unequal access to information, such as job recruitment or product quality assessment.

Professor: Let me give you an example from the used car market. Suppose you want to buy a used car, but you can't tell if it's reliable or a 'lemon.' The seller knows the car's history, but you don't. How can a seller of a good car convince you? They might offer a warranty—say, a free 1-year repair coverage. Now, a bad car seller wouldn't offer this because repairs would cost them too much. So the warranty acts as a signal—it's expensive for the seller to provide, but only for a good car is it worth it. You, as the buyer, see the warranty and think, 'This seller must have a reliable car,' and you're willing to pay a higher price. In this case, the warranty is a credible signal because it's costly for the seller to offer if the car is poor.