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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. Auction Theory
  4. /
  5. Scenario

Advanced Micro · advanced

A bidding ring quietly colludes

What moves on the Auction Theory diagram

  • First-price optimal bidshifts down (large)

Collusion removes effective rivals, so optimal bids fall well below value. Auction design (reserve prices, sealed bids) is partly a defence against exactly this.

Watch it animateQuiz yourself on Auction Theory

Step by step

  1. 1

    Rivals are what force bids toward true value.

  2. 2

    A ring forms: members agree not to bid against each other.

  3. 3

    Effective competition collapses and the bid function rotates down: heavy shading returns.

  4. 4

    The seller's revenue is quietly transferred to the ring, which is why bid rigging is a criminal cartel offence almost everywhere.

Where this shows up

Examiners ask this as: collusion, bidding ring, bid rigging, cartel auction, antique dealers ring.

Other scenarios on Auction Theory

Five more bidders join the auction →The item turns out to be worth more to you →