Market Microstructure: How Trades Execute and Prices Form
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Key Insights
- Understand the mechanics of order execution, bid-ask spreads, market making, and how electronic markets actually work.
Order Types and the Limit Order Book
Every trade requires a buyer and seller. The limit order book (LOB) matches them:
- Market orders — execute immediately at best available price (taker)
- Limit orders — execute only at specified price or better (maker)
- Stop orders — become market orders when price reaches threshold
- Iceberg orders — large orders split into smaller visible portions
The bid-ask spread reflects the cost of immediacy — the difference between the best buy (bid) and best sell (ask) prices.
Market Making
Market makers provide liquidity by continuously posting bid and ask quotes. Their profit comes from:
- Bid-ask spread capture — buying at bid, selling at ask
- Inventory management — rebalancing to avoid directional risk
- Adverse selection cost — losing to informed traders who know the true value
# Simplified market making P&L
spread_income = trades * half_spread
inventory_cost = position * price_change
adverse_selection = informed_trades * loss
net_pnl = spread_income - inventory_cost - adverse_selectionMarket Impact and Execution Quality
Large orders move prices. Understanding market impact is critical for institutional execution:
- Temporary impact — price impact that decays after execution
- Permanent impact — lasting price change from information revelation
- Implementation shortfall — difference between decision price and average execution price
Algorithms: TWAP (time-weighted), VWAP (volume-weighted), Implementation Shortfall, Iceberg, Sniper/Iceberg hybrid.
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Feynman Concept Cards
Master each building block: read the ELI5, explore the analogy, work the example, find your gaps, teach it back, build it.
Limit Order Book is a concept in foundations. In simple terms, Limit Order Book covers foundational knowledge in Markets. This markets concept addresses key topics in the foundational knowledge in markets domain. Also known as: LOB, order book. Related concepts i
Analogy
Example
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Explain Limit Order Book as if teaching a colleague who is new to foundations. Cover: what it is, how it works, and why it matters.
Create
Create a diagram that demonstrates Limit Order Book in a real-world foundations scenario. Walk through your design decisions.
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A diagram for Limit Order Book should include: 1. The core components of lob 2. How they interact 3. Expected outcomes or outputs
Market Microstructure is a concept in foundations. In simple terms, Market Microstructure covers foundational knowledge in Markets. This markets concept addresses key topics in the foundational knowledge in markets domain. Also known as: microstructure. Related concep
Analogy
Example
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Explain Market Microstructure as if teaching a colleague who is new to foundations. Cover: what it is, how it works, and why it matters.
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Create a diagram that demonstrates Market Microstructure in a real-world foundations scenario. Walk through your design decisions.
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A diagram for Market Microstructure should include: 1. The core components of market microstructure 2. How they interact 3. Expected outcomes or outputs
Order Types & Execution is a concept in foundations. In simple terms, Order Types & Execution covers foundational knowledge in Markets. This markets concept addresses key topics in the foundational knowledge in markets domain. Also known as: market order, limit order, s
Analogy
Example
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Explain Order Types & Execution as if teaching a colleague who is new to foundations. Cover: what it is, how it works, and why it matters.
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Create a diagram that demonstrates Order Types & Execution in a real-world foundations scenario. Walk through your design decisions.
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A diagram for Order Types & Execution should include: 1. The core components of order types 2. How they interact 3. Expected outcomes or outputs
Order Book Dynamics is a concept in market microstructure. In simple terms, Order Book Dynamics covers market microstructure within Markets. This markets concept addresses key topics in the market microstructure within markets domain. Also known as: LOB, limit order book, ord
Analogy
Example
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Explain Order Book Dynamics as if teaching a colleague who is new to market microstructure. Cover: what it is, how it works, and why it matters.
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Create a diagram that demonstrates Order Book Dynamics in a real-world market microstructure scenario. Walk through your design decisions.
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A diagram for Order Book Dynamics should include: 1. The core components of order book 2. How they interact 3. Expected outcomes or outputs
Apache Iceberg is a concept in advanced techniques. In simple terms, Apache Iceberg covers advanced techniques in Data Engineering. This data engineering concept addresses key topics in the advanced techniques in data engineering domain. Also known as: Iceberg, table f
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Explain Apache Iceberg as if teaching a colleague who is new to advanced techniques. Cover: what it is, how it works, and why it matters.
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