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Economic models you can actually see move. Every curve is computed and every shift is verified. Built for students who want intuition, not just diagrams.

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Educational purposes only, not financial advice. Graphl teaches which economic framework applies and how its mechanism works; it does not solve assessment problems for you.

  1. Library
  2. /
  3. Adverse Selection (Lemons Problem)
  4. /
  5. Scenario

Advanced Micro · intermediate

Mandatory warranties reassure buyers

What moves on the Adverse Selection (Lemons Problem) diagram

  • Buyers' willingness to payshifts up (small)
  • Price good-car owners needshifts down (small)

Warranties act as a credible signal: costly for lemon owners, cheap for good-car owners. Both sides' curves move toward more high-quality trade.

Watch it animateQuiz yourself on Adverse Selection (Lemons Problem)

Step by step

  1. 1

    A warranty is cheap to offer on a good car and expensive on a lemon.

  2. 2

    The law makes warranties mandatory.

  3. 3

    Buyers pay more (protection raises willingness to pay), and good-car owners can accept a bit less since the warranty certifies their car.

  4. 4

    Both moves raise the share of good cars traded. Warranties work by making honesty cheaper than lying.

Where this shows up

Examiners ask this as: warranty, mandatory guarantee, lemon laws, consumer protection, money back guarantee.

Other scenarios on Adverse Selection (Lemons Problem)

Vehicle history reports go mainstream →An odometer-fraud scandal torches trust →