Module 5 · Portfolio Management

The Behavioral Biases of Individuals

EN: Cognitive errors and emotional biases — and how to mitigate them.
VN: Sai lệch nhận thức và cảm xúc — cách giảm thiểu.

1. Cognitive Errors (Information Processing) Concept

About: Belief perseverance (conservatism, confirmation, representativeness) and information processing (anchoring, mental accounting, framing, availability).Tóm tắt: Cognitive: belief perseverance + information processing.

Belief perseverance

  • Conservatism Slow to update on new info.
  • Confirmation Seek info that confirms existing belief.
  • Representativeness Stereotypes, base-rate neglect.
  • Illusion of control Overestimate ability to influence outcomes.
  • Hindsight "I knew it all along" — overconfidence in retrospective accuracy.

Information processing

  • Anchoring Stick to initial reference (e.g. purchase price).
  • Mental accounting Treat money differently based on source/intended use.
  • Framing Decisions change based on how options are presented.
  • Availability Rely on easily recalled examples.

2. Emotional Biases Concept

About: Loss aversion, overconfidence, self-control, status quo, endowment, regret aversion. Harder to correct than cognitive errors — manage rather than fix.Tóm tắt: Loss aversion, overconfidence, self-control, status quo, endowment, regret. Khó sửa hơn cognitive.
  • Loss aversion Pain of loss > pleasure of equivalent gain.
  • Overconfidence Overestimate own ability.
  • Self-control Inability to delay gratification.
  • Status quo Bias toward current state.
  • Endowment Value something more once owned.
  • Regret aversion Avoid actions that may cause regret.

3. Mitigation Concept

About: Cognitive errors → education + structured processes (checklists, rules). Emotional biases → adapt rather than correct (especially with private wealth clients).Tóm tắt: Cognitive: giáo dục + checklist. Emotional: thích nghi hơn sửa (đặc biệt với khách giàu).

Cognitive errors can typically be corrected with education and structured decision processes (checklists, rules). Emotional biases are harder to overcome — typically the manager adapts to rather than corrects them, especially with private wealth clients.

Practice problem Practice

Practice problem

An investor refuses to sell a losing stock because she 'paid $50 for it and won't sell below that price'. Which bias?

Show solution
Stuck on initial reference price = anchoring.
Holding losers too long (refusing to realize loss) = disposition effect / loss aversion.
Anchoring (with loss aversion)