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Liquidation incentives after execution costs

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Start with the idea

A liquidation bonus compensates a liquidator for repaying debt and disposing of collateral. The headline bonus is not net profit.

Symbols, units & horizon
  • D_repay: USD debt repaid
  • b: quoted collateral bonus fraction
  • s: collateral sale discount/slippage fraction relative to quoted value
  • G: gas and other fixed USD costs
  • Π: realized scenario USD profit

When and why to use this

Investigate whether liquidation incentives remain viable under thin collateral liquidity and high fees.

A liquidation bonus compensates a liquidator for repaying debt and disposing of collateral. The headline bonus is not net profit.

Assume the liquidator repays a fixed dollar debt amount and receives collateral quoted at that amount plus a bonus. A discount on actual collateral sale can consume the bonus.

Add gas, failed-transaction costs and financing. Close-factor limits, oracle updates and competing liquidators affect whether the operation is available and profitable. This is an economics model; it does not submit transactions.

Π=Drepay(1+b)(1−s)−Drepay−G
Model assumptions, derivation and arithmetic

Liquidation incentives after execution costs

  1. Value received collateral as repaid debt times one plus bonus.
  2. Apply the attainable-sale fraction one minus slippage.
  3. Subtract repaid debt and fixed execution costs.
Work it by hand

Repay $1,000, bonus .05, sale discount .02 and gas $10. Sale proceeds=1050×.98=$1,029; profit=1029−1000−10=$19.

Apply it in a strategy

  • Investigate whether liquidation incentives remain viable under thin collateral liquidity and high fees.
  • Record the input timestamp, executable quantity, currency and horizon. Reconcile the result with a cash-flow or state table.
  • Stress this failure condition: Oracle collateral value may exceed attainable sale value, and failed attempts can still incur costs.

Research deliverable

Build and explain a liquidation incentives after execution costs worksheet. Investigate whether liquidation incentives remain viable under thin collateral liquidity and high fees.

Evidence boundary: Synthetic arithmetic and scenarios illustrate mechanics. They are not historical returns, a paper replication, or evidence of an executable edge. Research sources and their access limitations are recorded at the end of this module.

Primary research and operational references · reviewed 12 September 2026

Further reading: Milionis et al. — Automated Market Making and Loss-Versus-Rebalancing ↗

arXiv manuscript v6, revised 20 August 2026; publication status beyond this record not checked · Review: Abstract-only review 2026-09-12. Markets/data: Continuous-time model and Uniswap v2 ETH–USDC illustration; empirical sample dates not verified. Interpretation: Separates inventory market exposure from fees and adverse selection against a rebalancing benchmark. Limits: Abstract-only access; no empirical magnitude is used here. Discrete block trading, fees and oracle changes alter a continuous model. No independent replication performed.

Further reading: Uniswap — V2 pricing ↗

Official protocol documentation, V2 · Review: Documentation inspected 2026-09-12. Markets/data: Constant-product pools; no historical sample. Interpretation: Operational reference for reserve-based swap arithmetic and external price checks. Limits: The lessons label simplified fee and execution assumptions; other pool versions require different formulas. No independent replication performed.

Further reading: Aave — V3 overview ↗

Official protocol documentation, V3 · Review: Overview inspected 2026-09-12. Markets/data: Lending protocol mechanics; no empirical sample. Interpretation: Starting point for collateral, debt and health-factor research. Limits: Parameters differ by network, asset and governance state. Examples are generic lending models, not copied live parameters. No independent replication performed.

Research sources, review dates and limitations

Python implementation

Self-contained teaching example. Python 3.10+; dependencies and input conventions are shown in the code and notation. Run in your own Python environment.

# Python 3.10+; standard library unless NumPy is imported below.
# Inputs and outputs use the units defined in this lesson. Synthetic teaching example.
def liquidation_economics(debt,bonus,slippage,gas):
    if min(debt,bonus,gas)<0 or not 0<=slippage<1: raise ValueError("Invalid liquidation inputs")
    return debt*(1+bonus)*(1-slippage)-debt-gas

print(liquidation_economics(1000,.05,.02,10))

Continue learning

DeFi: AMMs, Liquidity Provision and Lending — all lessons
  1. Constant-product swaps with an input fee
  2. LP inventory after price changes
  3. LP value versus holding the original tokens
  4. Concentrated liquidity and range boundaries
  5. LVR and the price of stale inventory
  6. Lending utilization and rate response
  7. Collateral health factor and correlated shocks
  8. Liquidation incentives after execution costs

Quantitative finance and development glossary · Python resources and libraries · Research sources and limitations