11 — Herd & Social

Herd Behavior#

◐ Behavioral
◆ The PatternFollowing the crowd's actions rather than your own analysis.

Herd behavior — following the crowd's actions regardless of your own analysis.

Why we herd:
Evolutionary: safety in numbers (wildebeest at the river)
Informational: "They must know something I don't"
Social: fear of standing out, career risk ("no one got fired for buying IBM")

Market impact: Creates momentum that overshoots fair value in both directions

Keynes: "It is better for reputation to fail conventionally than to succeed unconventionally."

Pattern bridge: Following the crowd is a collective reward signal — the market’s version of RLHF. In statistics, it produces spurious correlation as everyone moves together.
When to use this
Use when: You notice everyone around you talking about the same trade. Social media is flooded with one-directional conviction. Volume spikes massively with no fundamental catalyst. A contrarian position has become very painful.
Skip when: The "herd" is responding to genuine fundamental changes (earnings beat, regulatory approval). Early in a trend — herding is most dangerous at extremes, not at the start. In highly efficient markets (large-cap liquid stocks) where herding is arbitraged away quickly.
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