The market's biggest risk is you.

Meet the two characters in your head: System 1, fast and automatic and always talking, and System 2, slow and effortful and usually asleep. Almost every judgment error starts when System 1 answers a hard question with an easy one. Learn its favourite shortcuts — availability, representativeness, anchoring — and why knowing about them isn't enough to switch them off.

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   Level 1 · ▶ NEXT The Two Systems ★★★ ◆
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   Level 2 Substitution & the Lazy Controller ★★★ ◆◆ 🧩 Builds on L01
3. 📰
   Level 3 The Availability Heuristic ★★★ ◆◆ 🧩 Builds on L02
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   Level 4 Representativeness & Base Rates ★★★ ◆◆◆ 🧩 Builds on L03
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   Level 5 Anchoring & Adjustment ★★★ ◆◆ 🧩 Builds on L04
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   Level 6 · EXAM Two Systems Exam ★★★ ◆◆◆ 🧩 Builds on L05

Kahneman and Tversky's Nobel idea: people don't feel wealth, they feel changes — gains and losses measured against a reference point, with losses hurting about twice as much. That single asymmetry explains why we take dumb risks to avoid a loss, why the same choice flips when you reframe it, and why we can't let go of what we own or what we've already spent.

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   Level 7 Value, Not Wealth ★★★ ◆◆ 🧩 Builds on L06
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   Level 8 Loss Aversion & the Endowment Effect ★★★ ◆◆ 🧩 Builds on L07
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   Level 9 Framing ★★★ ◆◆ 🧩 Builds on L08
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   Level 10 Probability Weighting & the Fourfold Pattern ★★★ ◆◆◆ 🧩 Builds on L09
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   Level 11 The Sunk-Cost Fallacy ★★★ ◆◆ 🧩 Builds on L10
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   Level 12 · EXAM Prospect Theory Exam ★★★ ◆◆◆ 🧩 Builds on L11

Now watch the biases loose in real markets. Overconfidence makes us trade too much and plan too optimistically; hindsight and confirmation rewrite the past and filter the present; mental accounting splits fungible money into leaky buckets; herding turns individuals into a crowd; and the disposition effect makes us sell winners and marry losers. This is behavioral finance where it costs money.

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   Level 13 Overconfidence & Calibration ★★★ ◆◆◆ 🧩 Builds on L12
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   Level 14 Hindsight & Confirmation ★★★ ◆◆ 🧩 Builds on L13
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   Level 15 Mental Accounting ★★★ ◆◆◆ 🧩 Builds on L14
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   Level 16 Herding & Social Proof ★★★ ◆◆ 🧩 Builds on L15
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   Level 17 The Disposition Effect ★★★ ◆◆◆ 🧩 Builds on L16
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   Level 18 · EXAM Biases in the Wild Exam ★★★ ◆◆◆ 🧩 Builds on L17

Zoom out to the whole market. Are prices always right? Shiller says no — feedback loops and new-era stories inflate bubbles, and the smart money can't always short them back to earth. Then turn the lens on yourself: nudges and choice architecture that steer without forcing, and the practical debiasing tricks — outside view, pre-mortems, rules — that help a fast mind think slow. Finish by diagnosing the bias in the wild.

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   Level 19 Are Markets Efficient? ★★★ ◆◆◆ 🧩 Builds on L18
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   Level 20 Bubbles & Irrational Exuberance ★★★ ◆◆◆ 🧩 Builds on L19
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   Level 21 Limits to Arbitrage ★★★ ◆◆◆◆ 🧩 Builds on L20
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   Level 22 Nudges & Choice Architecture ★★★ ◆◆ 🧩 Builds on L21
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   Level 23 Debiasing Yourself ★★★ ◆◆◆ 🧩 Builds on L22
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   Level 24 · EXAM Final Boss: Diagnose the Bias ★★★ ◆◆◆◆ 🧩 Builds on L23