Trading Psychology

A plan followed inconsistently is not a plan. Markets provide continuous feedback, much of it random, and human cognition is poorly adapted to that environment. Recognising the specific failure modes is more useful than resolving to be disciplined.

Four biases that show up repeatedly

Loss aversion

Losses register roughly twice as strongly as equivalent gains. In practice this produces the classic pattern of cutting winners quickly to secure relief while holding losers in the hope of avoiding the feeling of being wrong — the exact inverse of most viable strategies.

Recency bias

The last three trades feel like evidence about the strategy. They are not. Small samples in noisy systems carry almost no information, yet they drive most impulsive rule changes.

Confirmation bias

Once a position exists, the mind quietly filters incoming information in its favour. A written invalidation level, set before entry, is the most reliable countermeasure because it removes the need to reassess under emotional load.

Revenge trading

After a painful loss, urgency to recover replaces the plan. Position sizes grow, criteria loosen, and a single bad hour becomes a bad month. Predefined stop-for-the-day rules exist for precisely this state.

Building behavioural infrastructure

• Write the plan before the session, not during it.
• Use a pre-trade checklist that must be completed in order.
• Record emotional state alongside each trade in a journal.
• Set a daily loss limit that ends the session automatically.
• Review in batches, when the emotional charge has faded.

Discipline is not willpower applied harder. It is an environment designed so that fewer decisions have to be made under pressure.

Educational disclaimer: this article discusses general behavioural concepts and is not financial, investment, trading or psychological advice.