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Graphl

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 · intro

Five more bidders join the auction

What moves on the Auction Theory diagram

  • First-price optimal bidshifts up (large)

More rivals raise the chance that shading loses you the auction. Optimal bids climb toward true value: competition transfers surplus from bidders to the seller.

Watch it animateQuiz yourself on Auction Theory

Step by step

  1. 1

    With few rivals you can shade your bid well below your value and still often win.

  2. 2

    Five more bidders show up.

  3. 3

    The optimal bid function rotates up toward the 45-degree line: shading is now dangerous.

  4. 4

    With many bidders, first-price auctions squeeze nearly all the surplus from winners. Sellers love a crowd for exactly this reason.

Where this shows up

Examiners ask this as: more bidders, competitive auction, bidding war, crowded auction, many rivals.

Other scenarios on Auction Theory

The item turns out to be worth more to you →A bidding ring quietly colludes →